User manual BOSCH GWH-635-ES

GWH-635-ES INDOOR MODEL Temperature Modulated with Electronic Ignition Suitable for heating potable water only - Not approved for space heating purposes (Intended for variable flow applications) GWH-635-ES-N - Natural Gas GWH-635-ES-L - Liquefied Petroleum (LP) Gas Warning: If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or death. Do not store or use gasoline or other flammable vapor and liquids in the vicinity of this or any other appliance. Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information consult a qualified installer, service agency or the gas supplier. In the Commonwealth of Massachusetts this product must be installed by a licensed plumber or gas fitter. Upon completion of the installation, these instructions should be handed to the user of the appliance for future reference. What to do if you smell gas · Close gas valve. Open windows. · Do not try to light any appliance. · Do not touch any electrical switch; do not use any phone in your building. · If you cannot reach your gas supplier, call the fire department. · Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions. · Installation and service must be performed by a qualified installer, service agency or the gas supplier. 6 720 607 072 US (05.12) AL Index Index 1 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.9.1 2.10 2.11 2.12 2.12.1 2.12.2 2.12.3 2.13 2.14 2.15 2.16 2.17 3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 4 5 6 7 8 8.1 8.2 8.3 9 Warning Appliance details Features GWH-635-ES Specifications (Technical data) Dimensions and Minimum installation clearances General rules to follow for safe operation Proper location for installing your heater Clearances Mounting installation Combustion air requirements Venting Venting options Gas piping & connections Gas line sizing Measuring gas pressure Connecting Manometer Static Pressure Test Operating Pressure Test Water connections Electrical connections Operating instructions For your safety read before operating your water heater Lighting and operating instructions Operation instructions Power Temperature selection Use of remote control accessory Operation Reset button Program button Locked condition Maintenance and service Troubleshooting Electrical diagram GWH-635-ES Functional scheme Interior components diagram and parts list Interior components Components diagram Parts list 2 4 4 4 6 7 7 8 8 8 9 12 15 17 17 17 17 17 18 19 19 19 19 21 21 21 23 23 23 23 23 24 24 27 28 29 29 30 31 1 Warning Warning: If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or death. Warning: Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information consult a qualified installer, service agency or the gas supplier. Upon completion of the installation, these instructions should be handed to the user of the appliance for future reference. Featuring Electronic Ignition and Power Venting For your safety Do not store or use gasoline or other flammable, combustible or corrosive vapors and liquids in the vicinity of this or any other appliance. Warning: Carefully plan where you install the heater. Correct combustion air supply and flue pipe installation are very important. If a gas appliance is not installed correctly, fatal accidents can result from lack of air, carbon monoxide poisoning or fire. Warning: Exhaust gas must be vented to outside using proper vent material suitable for category III vent systems and temperatures up to 480°F. Vent and combustion air connector piping must be sealed gas-tight to prevent possibility of flue gas spillage, carbon monoxide emissions and risk of fire, resulting in severe personal injury or death. Warning: Place the heater in a location where water leaks will do NO DAMAGE to adjacent areas or lower floors. Special adjustment for measuring and adjusting CO2 levels 32 Protecting the environment 34 10 11 Fifteen Year Limited Warranty 35 2 6 720 607 072 Warning Warning: Field wiring connections and electrical grounding must comply with local codes, or in the absence of local codes, with the latest edition of the National Electric Code, ANSI/NFPA 70, or in Canada, all electrical wiring must comply with the local codes and the Canadian Electrical Code, CSA C22.1 Part 1. Warning: Shock hazard line voltage is present. Before servicing the water heater, turn off the electrical power to the water heater at the main disconnect or circuit breaker. Failure to do so could result in severe personal injury or death. What to do if you smell gas · Close gas valve. Open windows. · Do not try to light any appliance. · Do not touch any electrical switch; do not use any phone in your building. · Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions. · If you cannot reach your gas supplier, call the fire department. · Installation and service must be performed by a qualified installer, service agency or the gas supplier. Warning: The heater must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures equal to or more than 0.5 psig. FCC: This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. Caution: Any changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. Fig. 1 Fig. 2 6 720 607 072 3 Appliance details 2 2.1 Parts Appliance details Features 2.2 GWH-635-ES Specifications (Technical data) · Touch Pad interface control · High power pre-mix compact burner with low Nox emissions · Modulating Gas Valve with constant gas:air ratio control · Modulating water valve for improved comfort and temperature control. Safety · Flame sensor (ionization) rod · Overheat sensor · Temperature limiter · Fan speed monitoring. High Quality Materials for Long Working Life · Copper heat exchanger · High efficiency Ceramat Burner · Compact space saver: mounts on a wall with a supplied bracket. · Easily removable one-piece cover. Features · LCD Display · On/Off and Temperature control switches · Reset button · Program Key (Selectable temperature default) · Failure codes for easy diagnostic and repair. Accessories · Optional wireless remote control accessory to operate with the appliance · Vent termination kit. Approved in US/Canada Capacity Maximum flow rate: 6.35 GPM (24 l/min) at a 45°F (25°C) rise. Maximum output 142,968 Btu/h (41.8 kW) Maximum input 175,000 Btu/h (51.2 kW) Efficiency in % Recovery efficiency 86.5% Min. Output 31,131 Btu/h (9.1 kW) Temperature Control Selection range: 100°F (38°C) - 140°F (60°C) Default temperature: 122°F (50°C) Stability: +/- 2°F (+/- 1°C) Gas Requirement Gas connection (inches) - ¾" Inlet gas pressure under operation (with a high hot water flow rate)* · Propane: 11" - 14" water column · Natural Gas: 5" - 14" water column. * To measure Gas Pressure, see Measuring Gas Pressure, chapter 2.12. Venting A condensate trap is integrated into the exhaust flue gas collar of the heater, the supplied condensate drain tube must be installed to it for proper removal of condensate from the trap. See chapter 2.9 for Venting. Water · Hot water connection (inches) - ¾" · Cold water connection (inches) - ¾" · Water valve material: Polymer (PPS) (Polypropylene Sulfid) · Minimum water flow: 0.8 gallon/minute (3 l/m) · Minimum recommended water pressure: 30 PSI (2.07 bar) · Connections: ­ Bottom of heater i BOSCH is constantly improving its products, therefore specifications are subject to change without prior notice. 4 6 720 607 072 Appliance details Combustion · NOx 55 ppm · CO 250 ppm · CO2 level set from factory, see chapter 9. Dimensions · Depth (in): 8 ½" (220 mm) · Width (in): 15 ¾" (400 mm) · Height (in): 23 ½" (600 mm) · Weight: 47 pounds (21 kg). Gas types Natural Gas. LP Gas. Converting the gas type can only be done by a certified gas technician with a calibrated CO2 analyzer. Call BBTNA for conversion instructions. Voltage 120 V AC (50/60 Hz) Amperage IDLE - 40 mA Operation - 2,5 A Noise 50 db (A) Safety devices · Flame failure device (ionization flame rod sensor) · Pressure relief valve (supplied with heater) · Over heat prevention (temperature limiter). Water resistant IP X4 (protection against water drops) UNPACKING THE GWH-635-ES HEATER This heater is packed securely. The box includes: · Pressure relief valve (150 psi / 200,000 Btu rating) · Bracket for wall hanging the heater · Exhaust vent adaptor (with 4 screws and gasket provided) · Condensate drain tube kit · Combustion air inlet adaptor (with 3 screws and gasket provided) · Plastic decal shields for covering front cover screws and control panel, installer should affix these decals to the front of the unit after installation is complete. See Fig. 3 · Installation manual · Product registration card · Energy Guide label. Do not lose this manual. Please complete and return the enclosed product registration card. Before installing the unit, be certain you have the correct heater for your type of Gas - Propane or Natural Gas. Identification labels are found on the shipping box, and on the rating plate which is located on the right side panel of the cover. To remove front cover · Loosen the two Philips head screws located on front panel (beneath plastic decal shields if they are already attached, see Fig. 3) · Lift front cover panel upward and remove. Plastic decals Fig. 3 Remove front cover The GWH-635-ES is not approved or designed for: · Manufactured (mobile) homes, RV's or boats · Heating or other recirculating/pumping applications* · Outdoor installation (use only Outdoor Model GWH635-ESO) · Solar/preheat backup or high temperature booster use. * This includes domestic hot water circulator pump loop systems that may previously exist in a home hot water system. The use of a small electric mini-tank (4-6 gallon size) should be used for this application; when designed so the pump will circulate the hot water in the mini-tank only and through the building's hot water return loop (timed or thermostatic controlled operation of the pump is commonly done). The GWH-635-ES should be plumbed in line before the mini-tank water heater, contact BBTNA if further instruction is needed. 6 720 607 072 5 Appliance details 2.3 Dimensions and Minimum installation clearances Fig. 4 1 2 3 4 5 6 Dimensions Cover On/Off switch Reset button LCD display Program button Temperature buttons Fig. 5 Minimum clearances Model GWH-635-ES TOP (A) FRONT (B) BACK SIDES FLOOR (C) VENT DIAMETER 12" 1" 0" 1" 12" 3" Table 1 Minimum clearances 6 6 720 607 072 Appliance details 2.4 General rules to follow for safe operation 2.5 Proper location for installing your heater B 1. You should follow these instructions when you install your heater. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada: The Installation should conform with CGA B149.(1,2) INSTALLATION CODES and /or local installation codes. B 2. Carefully plan where you install the heater. Correct combustion air supply and vent pipe installation are very important. If not installed correctly, fatal accidents can be caused by lack of air, carbon monoxide poisoning or fire. B 3. When the unit is installed indoors and ROOM SEALED (twin pipe) it is permitted to be located in bathrooms, bedrooms and occupied rooms that are normally kept closed. See chapter 2.9. If the unit will be installed indoors and use indoor combustion air, the place where you install the heater must have enough ventilation. The National Fire Codes do not allow UNSEALED gas fired water heater installations in bathrooms, bedrooms or any occupied rooms normally kept closed. See chapter 2.5 and 2.8. B 4. You must vent your heater. See section on VENTING. B 5. The appliance and its gas connection must be leak tested before placing the appliance in operation. The appliance must be isolated from the gas supply piping system by closing its individual manual gas shutoff valve (not supplied with heater) during any pressure testing at pressures in excess of ½ Psig (3.5 kPa). B 6. Keep water heater area clear and free from combustibles and flammable liquids. Do not locate the heater over any material which might burn. B 7. Correct gas pressure is critical for the optimum operation of this heater. Gas piping must be sized to provide the required pressure at the maximum output of the heater, while all the other gas appliances are in operation. Check with your local gas supplier, and see the section on connecting the gas supply. B 8. Should overheating occur or the gas supply fail to shut off, turn off the gas supply at the manual gas shut off valve, on the gas line. Note: manual gas shutoff valve is not supplied with the heater. B 9. Do not use this appliance if any part has been underwater. Immediately call a qualified service technician to inspect the appliance and to replace any part of the control system and any gas control which has been underwater Carefully select the location of the water heater. For your safety and for proper heater operation, you must provide combustion air to the heater and a proper exhaust vent system. Follow the guidelines below: B 1. Locate the heater where venting, gas and plumbing connections are feasible and convenient. B 2. It is strongly recommended that the heater be installed as a ROOM SEALED heater (twin pipe). If the heater will be installed as an UNSEALED heater (single pipe) than National building codes require that you do not install this appliance in bathrooms, bedrooms or any occupied rooms normally kept closed. Heaters that are UNSEALED require a considerable amount of combustion air, see chapter 2.8. If installing the heater UNSEALED within a laundry room, be certain that the dryer is properly vented. Failure to properly vent a dryer could result in a gradual accumulation of lint build up inside the combustion chamber of the heater. B 3. The hot water lines should be kept short to save energy. Centrally locating the water heater is best. It is always best to have hot water lines insulated. Warning: The water in this water heater is cold and always remains cold except for the times that hot water is being used DO NOT INSTALL IN AN AREA WHERE IT COULD FREEZE. Drain the heater entirely if freezing temperatures are anticipated in area where heater is installed by disconnecting both the inlet and outlet connections at the bottom of heater. To prevent any freeze damage, introduce short bursts of compressed air (20-40psi) through these connections to remove the residual water in the horizontal pipes and water valve. Warning: Flammable materials, gasoline, pressurized containers, or any other items or articles that are potential fire hazards must NOT be placed on or adjacent to the heater. The appliance area must be kept free of all combustible materials, gasoline and other flammable vapors and liquids. 6 720 607 072 7 Appliance details 2.6 Clearances The GWH-635-ES is design certified for installation on a combustible wall (see 2.7 Mounting installation) provided the floor covering below the heater is noncombustible. For installations in an alcove or closet, maintain the minimum clearances to combustible and non-combustible materials listed below. See also Fig. 5. A. Top 12 inches (306 mm) B. Front 1 inches (25 mm) C. Back 0 inches D. Sides 1 inches (25 mm) E. Bottom 12 inches (306 mm) Clearances from any exhaust vent pipe are dependent upon the clearance requirements of the stainless steel vent pipe manufacturer. Single wall stainless steel (AL29-4C) vent pipe (vent type rated for Category III appliances) must be used when exhaust venting this appliance. See 2.9 Venting. 2.7 Mounting installation Warning: before starting installation: B check that there are no loose parts inside the appliance B ensure that gas pipe, gas valve, mixer, fan and burner have no damage and are properly fitted. Fig. 6 Mounting the heater 2.8 Combustion air requirements i Front cover should be removed (see instructions on page 4) in order to inspect components visually. The GWH-635-ES is design certified for mounting on a wall. Secure the wall mounting bracket provided with the heater to a wall surface. See Fig. 6. Do not install this appliance on a carpeted wall or over floor covering which is combustible, such as carpet. The heater must be mounted on a wall using appropriate anchoring materials. If the mounting bracket is unable to line up on two wall studs it is recommended that support board(s), either 1x4's or ½" (minimum) plywood first be attached across a pair of studs and then the heater should be attached to the support boards. The heater should be kept level on the wall surface. See Fig. 6. Expansion and contraction of piping due to changing water temperature in the pipes imparts movement to the heater which, if mounted directly to a brittle, friable board, such as plasterboard, can cause failure of mounting. Before installing the unit, be certain you have the correct heater for your type of Gas - Propane or Natural Gas. Identification labels are found on the shipping box, and on the rating plate which is located on the right side panel of the cover. The GWH-635-ES is a sealed water heater and it's recommended that outdoor combustion air be supplied to the unit (TWIN PIPE SYSTEM). The combustion air pipe system may be constructed of either 3" aluminum or aluminum flex, PVC or galvanized pipe. See Fig. 10, 12 and 13. Select a point for building penetration being sure that a 3 foot minimum distance is maintained between the combustion air terminator and the exhaust vent terminator, see Fig. 16 Letter I. NOTE: Observe all local building codes when penetrating a building wall. NOTE: The combustion air inlet location on the side of a building must never be less than 3 feet away from the units exhaust vent terminator, see Fig. 16 Table 4. The heater has the ability to operate without combustion air being piped to it from the outside, provided there is an adequate amount of combustion air available in the room area. Observe the following instructions concerning combustion air when following the SINGLE PIPE (exhaust venting only) SYSTEM only and follow Fig. 14 and 15 for proper setup. · Appliances located in unconfined spaces: ­ a) An unconfined space is one whose volume is greater than 50 cubic feet (1.42 cubic meter) per 1000 Btu per hour (292.81 Watts) of the combined rating of all appliances installed in the space. That would be 8750 cubic feet (247.8 cubic meter) for the GWH-635-ES alone. ­ b) In unconfined spaces in buildings of conventional frame, masonry, or metal 8 6 720 607 072 Appliance details construction, infiltration air is normally adequate to provide air for combustion. · Appliances located in confined spaces: The confined space must be provided with two permanent openings, one commencing within 12 inches (304.8mm) of the top and one commencing within 12 inches (304.8mm) of the bottom of the enclosure. Each opening must have a minimum free area of one square inch per: ­ 1000 Btu/hr (292.81 Watts) if all air is taken from inside the building ­ 2000 Btu/hr (585.62 Watts) if all air is taken from the outside by horizontal ducts ­ 4000 Btu/hr (1171.24 Watts)if all air is taken from the outside by direct openings or vertical ducts Or the confined space must be provided with one permanent opening or duct that is within 12 inches (304.8mm) of the ceiling of the enclosure. This opening must have a minimum free area of one square inch per: ­ 3000 Btu/hr (878.43 Watts) if all air is taken from the outside by a direct opening or vertical duct. Louvers, grills and screens have a blocking effect, when used, increase the sizes of your openings by 300% for wood louvers (as wood type will reduce the free air by 75%) and 40% for metal louvers (as metal will reduce the free air by 30%). Refer to the National Fuel Gas Code for complete information. In buildings of tight construction all air should be taken from outside. NOTE: It is not recommended to use interior room air (SINGLE PIPE vent system) in areas that commonly experience below freezing temperatures. Clothes dryers, furnaces, woodstoves, bathroom or kitchen fans or other gas appliances can create negative air pressure when operating by removing air from the building. Cold air will be drawn back into the building, and if drawn through the water heater a freezing situation may occur. TWIN PIPE (room sealed) method of venting is recommended, see page 12. NOTE: When installed in beauty shops, barber shops, or other facilities where chemicals that generate corrosive or flammable products such as aerosol sprays are routinely used, shall be installed as sealed unit following the TWIN PIPE SYSTEM method of venting. 2.9 Venting Warning: Do not reduce the vent (exhaust and combustion) pipe sizes and do not common vent with any other vented appliance or stove. NOTE: This appliance's exhaust must be vented to the outside1 with sealed stainless steel vent pipe (AL29-4C), the minimum vent length is 3 feet (a 90 degree vent elbow is equivalent to 2 ½ feet). The appliance's flue gasses are under positive pressure and must travel through a stainless steel 3" or 4" pipe that is sealed gas tight. NOTE: The exhaust collar on the water heater is 3" diameter and its collar must always be used, a 3" to 4" increaser will be required to be first connected to the exhaust collar when 4" venting is used. Different stainless steel vent manufacturer's have different joint systems, do not mix vent pipe or joining methods from different manufacturer's. Stainless steel vent pipe is equipped with sealing gaskets for ease of installation, proper safety and durability. The heater shall not be vented in combination with any other appliance; the appliance must only be vented with a dedicated sealed vent system. Z flex Protech Heat Fab BBTNA 3" VENTING 3" Horizontal Terminal 3" Vertical terminal 4" VENTING Requires a 3" to 4" Increaser 2SVSTB03 2SVSRCF03 FSTB3 FSRC3 9390 TEE 5300CI 2SVSTB03 2SVSRCF03 2SVI0304 FS0304TI 9374 2SVI0304 4" Horizontal terminal 2SVSRTF04 FSTB4 9490TEE FXHOOD 4" Vertical terminal 2SVSRCF04 FSRC4 5400CI ---------- Table 2 Terminals/Adapters Part Numbers Caution: The vent system must be installed by a qualified agency in accordance with these instructions. If improperly installed a hazardous condition such as explosion or Carbon Monoxide poisoning could result. BBTNA will not be responsible for improperly installed appliances. Establish vent clearances that comply with the vent manufacturer's specifications. In all cases follow local codes. See table 3. 6 720 607 072 9 Appliance details The maximum flue gas exhaust temperature on the GWH-635-ES is 437°F (225°C) Venting Options Exhaust vent diameter and material 3 or 4+ inch stainless steel (AL29-4C) sealed vent pipe 3 or 4+ inch stainless steel (AL29-4C) sealed vent pipe * Exhaust vent maximum length * Exhaust vent minimum length Combustion air pipe diameter and material Combustion air pipe maximum length Vent pipe clearances within an unenclosed space ** See vent manufacturer's specifications Vent pipe clearances within an enclosed space ** See vent manufacturer's specifications Room sealed (twin pipe) 26 feet (8 m) with one elbow. Less 2½ feet for each additional 90° elbow 26 feet (8 m) with one elbow. Less 2½ feet for each additional 90° elbow 3 feet 3 inch PVC, aluminum or galvanized pipe 26 feet (8 m) with one elbow. Less 2½ feet for each additional 90° elbow See chapter 2.8 Open combustion (single pipe) 3 feet See chapter 2.8 ** See vent manufacturer's specifications ** See vent manufacturer's specifications Exhaust vent is always fan assisted. Installation of exhaust vent and combustion air piping may be run vertically or horizontally and in separate directions if required. + The exhaust collar on the water heater is 3" diameter and its collar must always be used, a 3" to 4" increaser will be required to be first connected to the exhaust collar when 4" venting is used. * A maximum of three 90 degree elbows are permitted in both the exhaust and combustion air vent lengths. The total vent length must be reduced by 1 ¼ feet for every 45° elbow used in the vent system. ** Stainless steel (AL29-4C) vent pipe is manufacturerd by Z-Flex, Protech and Heat Fab. NOTE: clearance distances are variable depending if the vent pipe is installed in an enclosed or unenclosed space, the exhaust flue gas temperature and the orientation of the vent pipe. Table 3 Minimum exhaust vent size and length The appliance should be located as close to the point of termination as possible. The maximum vent length is 26 feet (8 m) with one 90 degree elbow. Subtract 2½ feet from the total vent length for each additional 90° elbow used (a maximum of three 90° elbows are permitted in the total vent length), or subtract 1 ¼ feet for every 45° elbow used. Horizontal sections of vent must pitch ¼" for every foot of horizontal length, to prevent the pooling of condensate, and be supported at 4 foot intervals with overhead hangers. Note: Listed thimbles or collars are necessary to pass through wall and ceiling partitions. If the vent system passes through combustible areas where the vent clearance requirements cannot be maintained, it is permissible to chase straight sections of sealed 3 inch single wall vent through 4 inch (or greater) Type-B vent. The distance to combustibles using this chase technique is 1 inch. Note: Type-B vent should never be used as the actual exhaust vent system for the appliance, as it is not gas tight. The minimum exhaust vent length is 3 feet. The use of a 90 degree elbow is equivalent to 2 ½ ft in vent length. The use of 45 degree elbow is equivalent to 1 ¼ ft in vent length. Fig. 7 Maximum exhaust vent and combustion air inlet lengths Fig. 8 10 6 720 607 072 Appliance details Note: reduce 2½ ft for each 90° elbow used after the first one, reduce 1 ¼ ft for each 45° elbow. Vent Safety System The GWH-635-ES will shut down if inadequate exhaust venting is detected or a lack of combustion air is provided to the unit; see troubleshooting section on page 24. See error code to confirm error, correct the problem and then reset the heater before operating. Attaching the exhaust and air inlet connection adaptors to the top of the heater Use of the external condensate drain tube kit (supplied with the heater) on the exhaust collar B The condensate drain tube kit must be used for all installation types. Failure to install condensate drain will void the warranty. B When installing the condensate drain tube kit at the exhaust collar (see diagram below), be sure to form a trap by means of a 3" (76.2 mm) loop filled with water. The supplied tube is 3/8" ID high temperature silicone and must be attached to the condensate tapping on the exhaust collar with its supplied gear clamp (first remove screw at tapping point). B To increase tube length, connect vinyl type tubing after the supplied tube. B The condensate must be disposed of according to local regulations. Condensate port on exhaust collar 1. Remove tapping screw Fig. 9 2. Fit tube with gear clamp 3. Coil tube into 3" circle with nylon tie (don't crimp tubing) and fill circle with water Fig. 11 Fig. 10 B Attach the flue gas exhaust accessory (8 705 504 114) to the top of the unit (position 1) using the 4 screws and gasket provided, and fully insert 3" stainless steel vent pipe into the accessory and tighten the clamp (position 2). B Attach the combustion air inlet accessory (8 705 504 115) to the top of the unit (position 3) using the 3 screws and gasket provided, and fully insert 3" combustion air pipe into the accessory and tighten the clamp (position 4). NOTE: The appliance has the possibility to mount the combustion air inlet accessory on the top right or on the top left side of the heater. The combustion air inlet that is not used must be kept sealed. 6 720 607 072 11 Appliance details 2.9.1 Venting options Installing this water heater as a room sealed (TWIN PIPE SYSTEM) is the recommended method. Contact BBTNA or dealer for available vent termination kits and vent materials for this water heater. Open combustion installation (SINGLE PIPE SYSTEM) Not recommended Chapter 2.8. in cold climate areas, see i Exhaust venting shall be done with 3" or 4" stainless steel (AL29-4C) vent pipe. Room sealed installation (TWIN PIPE SYSTEM) Fig. 14 Exhaust vent pipe: 26 ft (8 m) Fig. 12 Combustion air pipe: 26 ft (8 m) Exhaust vent pipe: 26 ft (8 m) Fig. 15 Exhaust vent pipe: A+B+C 23½ ft (7.2 m) Fig. 13 Combustion air pipe: 26 ft (8 m) Exhaust vent pipe: A+B+C 23½ ft (7.2 m) Note: reduce 2½ ft for each 90° elbow used after the first one, reduce 1 ¼ ft for each 45° elbow. A maximum of three 90-degree elbows are permitted in both the exhaust and combustion air vent lengths. The exhaust vent system must vent directly to the outside of the building and an adequate amount of indoor combustion air must be provided for this installation. See chapter 2.8. Connecting a one piece 90 degree elbow pipe to the combustion air inlet adaptor is necessary, this will prevent debris or objects from ever falling into the inlet opening. Note: reduce 2½ ft for each elbow used after the first one, reduce 1 ¼ ft for each 45° elbow. A maximum of three 90-degree elbows are permitted. i The exhaust vent pipe and combustion air pipe can be run vertically or horizontally. Maximum length for each individual pipe is 26 feet (8 m) with one elbow, for each additional 90° elbow after the first elbow you must reduce 2½ feet from the total vent length, or 1 ¼ feet for each 45° elbow. 12 6 720 607 072 Appliance details Recommended exhaust vent terminator position Fig. 16 Ref. A Description Directly below an opening; operable windows, doors and any nonmechanical fresh air openings Below a gutter, sanitary pipework or eaves Minimum distance 36 in 24 in 12 in 12 in 12 in 7 ft 24 in B Below a gutter, sanitary pipework or eaves, protected by metal shielding From any internal corner Above ground Above a paved sidewalk From an opposing wall or structure facing the termination C D* E From any other building opening, gas utility meter, service regulator or the like From a terminator facing a terminator Vertically between two exhaust vent terminators on the same wall Horizontally between two exhaust vent terminators on the same wall Horizontally from combustion air inlet of GWH-635-ES 36 in 48 in 60 in 12 in F G H I** Vertically above or below combustion air inlet of GWH-635-ES From the combustion air inlet of any other equipment 36 in 6 ft 12 in 12 in see ABOVE THE ROOF requirements on following page J K L From any external corner Horizontally from an opening; operable windows, doors and any non-mechanical fresh air openings Vertically from a wall, roof slope, or obstruction (venting through a flat or pitched roof) Table 4 * Subject to local codes and anticipated snow level ** Other equipment that operates with a mechanical air inlet may require greater distances, reference manufacturer's instructions 6 720 607 072 13 Appliance details Supporting the exhaust vent system i The venting materials and accessories required to properly install the water heater are available from BBTNA and their distributors. Fig. 17 Horizontal side wall venting installation (combustion air piping not being shown) Fig. 19 Vertical venting installation (combustion air piping not being shown) A condensate drain tube must be attached to the exhaust collar of the heater for all vent type applications, see page 11. Fig. 18 Above the roof clearance requirements from rain cap (combustion air piping not being shown) B A condensate drain tube must be attached to the exhaust collar of the heater for all vent type applications, see page 11. 14 6 720 607 072 Appliance details 2.10 Gas piping & connections Before connecting the gas supply, check the rating plate on the right side of the heater to be sure that the heater is rated for the same gas to which it will be connected. In the United States: The installation must conform with local codes or, in the absence of local codes, the National Fuel Gas Code ANSI Z223.1/NFPA 54. In Canada: The Installation should conform with CGA B149 INSTALLATION CODES and/or local installation codes. GAS LINE SIZING The gas supply piping should be sized according to the National Fuel Gas Code for a maximum draw of 175,000 BTUH. First determine the effective length of the gas supply line by measuring the actual length of piping, and then adding 5 ft. (1.52m) for every elbow or "T" to the actual length. Use the charts in Fig. 22 to determine the pipe diameter necessary to accommodate the BTU (Wh) demand of the unit. If there are more gas drawing appliances on the line, size according to the maximum amount of BTU (Wh) demand. Note: It is important that if any flexible gas line is used, above or below ground between the gas supply meter/ regulator and the water heater, that it be sized properly. Consult the gas sizing specification tables provided by the flexible gas line manufacturer and sample CSST flexible gas line tables in Figure 22. Fig. 20 Vertical venting installation - Masonry Chimney (combustion air piping not being shown) A condensate drain tube must be attached to the exhaust collar of the heater for all vent type applications, see page, see page 11. Inlet gas particle screen Gas piping Fig. 21 B Install a manual gas shut off valve, on the gas supply line. B The use of a union when connecting gas pipe to the gas inlet connection is critical, this will facilitate any necessary servicing and cleaning of the inlet gas particle screen. B Flexible gas line connectors are not recommended because they are commonly undersized and restrict gas flow. Oversize the diameter of any flexible gas appliance connector if one must be used. 6 720 607 072 15 Appliance details FOR NATURAL GAS Maximum Capacity of pipe in Cubic Feet of Gas per Hour for Gas Pressure of 0.5 Psig or less and a Pressure drop of 0.3 in Water Column (0.75mbar).(Based on a 0.60 Specific Gravity Gas) Btu numbers given in thousands. Follow boxed numbers for piping just one 635-ES (example: ¾" B.I. Natural Gas pipe for 20 ft (6.1m). will handle 190,000 btu's (55.7 kWh). For multiple appliances combine the total btu input load and then refer to applicable chart below. Nominal Iron Pipe Size, Internal Diameter 10 32 72 132 278 520 1050 1600 3050 20 22 49 92 190 350 730 1100 2100 30 18 40 73 152 285 590 890 1650 40 15 34 63 130 245 500 760 1450 50 14 30 56 115 215 440 670 60 12 27 50 105 195 400 610 70 11 25 46 96 180 370 560 80 11 23 43 90 170 350 530 990 90 10 22 40 84 160 320 490 930 100 9 21 38 79 150 305 460 870 125 8 18 34 72 130 275 410 780 150 8 17 31 64 120 250 380 710 175 7 15 28 59 110 225 350 650 200 6 14 26 55 100 210 320 610 Length of Black Iron Pipe, Feet inches inches 1/4 3/8 1/2 3/4 1 1 1/4 1 1/2 2 0.364 0.493 0.622 0.824 1.049 1.380 1.610 2.067 1270 1150 1050 Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet Tube size, inches 1/2 3/4 1 1 1/4 EHD* 10 18 EHD 82 23 EHD 161 30 EHD 330 37 EHD 639 20 58 116 231 456 30 47 96 188 374 40 41 83 162 325 50 37 75 144 292 60 34 68 131 267 * EHD = Equivalent Hydraulic Diameter. The greater the value of EHD, the greater the gas capacity of the tubing. FOR LP GAS Maximum Capacity of Pipe in Thousands of BTU per Hour of Undiluted Petroleum Gases (at 11 inches Water Column Inlet Pressure) (Based on a Pressure Drop of 0.5 Inch Water Column). * EHD = Equivalent Hydraulic Diameter. The greater the value of EHD, the greater the gas capacity of the tubing. Nominal Iron Pipe Size, Inches Length of Flexible Corrugated Stainless Steel Tubing (CSST), Feet Black Iron Pipe Length of Pipe, Feet 10 20 30 40 50 60 70 96 80 89 90 83 100 78 162 307 630 976 125 69 146 275 567 866 150 63 132 252 511 787 Tube size inches 1/2 3/4 1 1 1/4 EHD* 10 18 EHD 129 23 EHD 254 30 EHD 521 37 EHD 971 20 91 183 365 661 30 74 151 297 528 40 64 131 256 449 50 58 118 227 397 60 53 107 207 359 1/2 3/4 1 1 1/4 1 1/2 275 189 152 567 693 315 107 732 590 220 149 121 330 229 185 129 114 103 267 237 217 196 185 173 504 448 409 378 346 322 103 913 834 771 724 677 155 141 127 118 108 102 Maximum Capacity of Semi-Rigid (flexible, non Outside diameter Inch 3/8 1/2 5/8 3/4 10 39 92 20 26 62 30 21 50 corrugated) Tubing in Thousands of BTU per Hour of Undiluted Liquefied Petroleum Gases (at 11 inches Water Column Inlet Pressure). (Based on a Pressure Drop of 0.5 Inch Water Column) * Source National Fuel Gas Code NFPA 54, ANSI Z223.1 - No Additional Allowance is necessary for an ordinary number of fittings Copper Length of Tubing, Feet 40 19 41 90 50 _ 37 79 131 60 _ 35 72 70 _ 31 67 80 _ 29 62 90 _ 27 59 100 _ 26 55 90 199 131 329 216 107 181 145 121 112 104 95 Fig. 22 16 6 720 607 072 Appliance details 2.11 Gas line sizing B It is strongly recommended that the Natural Gas pipe be Black Iron pipe the entire distance from the outside meter to the inlet of the gas connection. ¾" Black Iron pipe up to 20 feet (6.1m) and 1" Black Iron pipe up to 70 feet (21.34m) distances. Flex line is NOT recommended, but if used, then oversize the diameter of the flex pipe, keep the length to a minimum and try to keep the flex line as straight as possible. B It is strongly recommended that the LP Gas pipe be semi-rigid copper or Black Iron pipe from the outside regulator to the inlet of the gas connection. For semirigid copper piping: 5/8" up to 10 feet (3.05m) and ¾" up to 30 feet (9.14m) distances. For Black Iron piping: ½" up to 20 feet (6.1m) and ¾" up to 80 feet (24.38m) distances. Flex line is NOT recommended, but if used, then oversize the diameter of the flex pipe, keep the length to a minimum and try to keep the flex line as straight as possible. 2.12 Measuring gas pressure 2.12.1 Connecting Manometer B Shut off gas. B Remove front cover and locate inlet gas pressure measuring point (see Fig. 24). B Loosen screw inside test point fitting (do not remove) and connect manometer tube on test point. 2.12.2 Static Pressure Test B Turn gas supply back on. B Operate all other gas appliances on same gas piping system at maximum output. B Record static gas pressure reading in table 5. 2.12.3 Operating Pressure Test B ON/OFF switch in position OFF (0). B Press and hold "Program" (M) button and turn ON/ OFF switch to ON position. i THESE FIGURES ARE FOR GWH-635ES SUPPLY ONLY, ALL OTHER APPLIANCES IN THE BUILDING MUST BE INCLUDED IN THE PIPE SIZING. National Fuel Gas Code requires that a sediment trap (drip leg) be installed on gas appliances not so equipped. Also, a manual gas shut off valve must be installed on the gas supply line within close proximity of the water heater and be visible from the water heater. Warning: The heater must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures equal to or more than 0.5 psig. The water heater must not be piped with gas supply pressures in excess of 0.5 psig. If overpressure has occurred, such as through improper testing of the gas lines or malfunction of the supply system, the gas valve must be checked for safe operation. When connections are made, check for gas leaks at all joints. Apply some soapy water to all gas fittings. Soap bubbles are a sign of a leak. Danger: If you have a leak, shut off the gas. Tighten appropriate fittings to stop leak. Turn the gas on and check again with a soapy solution. Never test for gas leaks using a match or flame. Fig. 23 B As soon as '188' is displayed, release "Program" button and the display should read P2. B Press , until P1 appears. Note: While in this mode the appliance will run constantly at maximum power and allow maximum water flow. B Turn on high volume of hot water flow (at least 6 gpm) and heater will ignite. B Record operating gas pressure reading in table 5. Gas pressures lower than 5" W.C. for Natural Gas or 11" W.C. for LPG will result in insufficient degree rise to the hot water being used, and must be corrected. See Gas Connections, chapter 2.10. Fig. 24 Gas pressure measuring (left tapping) 6 720 607 072 17 Appliance details Static Gas Pressure Reading (see Chapter 2.12) enter here: ___________________ Operating Gas Pressure Reading (see Chapter 2.12) enter here: ___________________ Table 5 HIGH ALTITUDE OPERATION Altitude Natural Gas: Liquid Propane: For operation at elevations above 2,000 ft (610 m) the equipment ratings shall be reduced at the rate of 4% for each 1,000 ft (305 m) above sea level 0 - 4,000 ft (0 - 1,219 m) no modification no modification local codes if more stringent). Never sweat any rigid piping directly to or beneath the water connections, damage can occur to the internal water valve from heating of the pipe. Plastics or other PEX type plumbing line materials are not suitable for connecting directly to the water heater. Keep water inlet and outlet pipes to no less than ¾" (19.05mm) diameter to allow the full flow capacity. If the cold and hot connections to the heater are reversed, the heater will not function. Be certain there are no loose particles or dirt in the piping. Blow out or flush the lines before connecting to the water heater. Full port valves should be installed on both the cold water supply and hot water outlet lines to facilitate servicing the heater (see Fig. 26). For installation on a private well system with the use of a pressure tank, the lowest pressure range setting recommended is 30-50 psi (2.07 and 3.45bar). Connecting the pressure relief valve (PRV) A listed pressure relief valve supplied with the heater must be installed at the time of installation. No valve is to be placed between the PRV and the heater. No reducing coupling or other restriction may be installed in the discharge line. The discharge line must be a minimum of 4" above a drain and installed such that it allows complete drainage of both the PRV and the line. The location of the PRV must be readily accessible for servicing or replacement, and be mounted as close to the water heater as possible. See Fig. 26. To install the PRV, a suitable fitting connected to an extension on a "T" fitting can be sweated to the hot water line. Support all piping. 4,000 ft - 7,000 ft (1,219 m - 2,134 m) CO2 adjustment with flue gas analyzer required See chapter 9 for instructions. Above 7,000 ft (above 2,134 m) Not approved Table 6 2.13 Water connections When facing the heater, the ¾" cold water inlet is on the bottom right and the hot water outlet is on the bottom left. Install the heater centrally in the building if possible and make hot water piping runs as short as possible. INLET FILTER SCREEN HOT COLD Fig. 25 B THE USE OF A UNION WHEN CONNECTING BOTH WATER PIPES TO THE INLET AND OUTLET CONNECTIONS IS RECOMMENDED, THIS WILL FACILITATE ANY NECESSARY SERVICING AND REQUIRED CLEANING OF THE INLET WATER PARTICLE SCREEN. Although water piping throughout the building may be other than copper, we recommend that copper, galvanized or suitably rated stainless steel flex line piping be used for the water heater connections (follow 18 Fig. 26 Plumbing Connections and Pressure Relief Valve 6 720 607 072 Appliance details 2.14 Electrical connections Warning: For safety reasons, disconnect the power supply to the heater before any service or testing is performed. Warning: This heater must be electrically grounded in accordance with the most recent edition of the National Electrical Code. NFPA 70. In Canada, all electrical wiring to the heater should be in accordance with local codes and the Canadian Electrical Code, CSA C22.1 Part 1. Do not rely on the gas or water piping to ground the metal parts of the heater. The GWH-635-ES requires an electrical power supply from a 120VAC 60Hz circuit and must be properly grounded. A means for switching off the 120VAC power supply must be provided. The heater is wired as shown in the wiring diagram (chapter 6, Fig. 37). 2.16 For your safety read before operating your water heater Warning: If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or loss of life. A. This appliance is equipped with electronic ignition for lighting the main burners. When turning the heater on, follow these instructions exactly. B. Before operating the unit, set the On/Off switch to the On ( I ) position. WHAT TO DO IF YOU SMELL GAS B Do not try to light any appliance. B Do not touch any electric switch; do not use any phone in your building. B Immediately call your gas supplier from a neighbors phone. Follow the gas supplier's instructions. B If you cannot reach your gas supplier, call the fire department. C. Use only your hand to turn the on/off control switch. Never use tools. Follow these instructions exactly. If control switch is jammed, close the gas supply and call a qualified service technician. Attempted forceful repair may result in a fire or explosion. D. Do not use this appliance if any part has been under water. Immediately call a qualified service technician to inspect the appliance and to replace any part of the control system and any gas control which has been under water. 2.15 Operating instructions B Before proceeding with the operation of the heater make sure that the system is filled with water. B Turn off power supply to heater. B Open the cold water inlet supply to the heater fully. B Open a hot water faucet to permit the water to fill the heater and the piping and to eliminate the air trapped in the system. B Close the hot water faucet after the water flows freely and all the air has escaped from the system. Turn on power supply to heater. The water heater is now ready to operate. 2.17 Lighting and operating instructions B 1. STOP! Read the previous safety information. B 2. The gas valve must be shut off by putting the ON/ OFF switch to position (0). Wait five (5) minutes to clear out any gas. If you smell gas, STOP! Follow "B" in the safety information above. If you do not smell gas, go to the next step. B 3. This appliance is equipped with electronic ignition for lighting the main burners. When turning the heater on, follow these instructions exactly. B 4. Set the ON/OFF switch to the (I) position. In this position, the water heater is ready to use. B 5. Open a hot water tap. B 6. The burners will remain on until the hot water tap is turned off. i NOTE: A default temperature setting of 122 F will appear on the display screen. 6 720 607 072 19 Appliance details i NOTE: on a first time initial installation or after gas line work has been done, existence of air in the gas line will cause ignition delay when the hot water is turned on. This will result in an error (EA) on the units display screen. This is normal. When this occurs, leave the hot water running and wait 3-5 seconds, then reset the unit (Fig. 26, pos. 2). Wait for (EA) to disappear. The heater will begin to attempt ignition again, if the (EA) reappears then repeat this same process until all air has been bled from the gas line. When the heater is in operation you will hear its power vent fan and burner operating. Upon turning off the hot water flow the power vent fan will continue to operate for up to 60 seconds to exhaust all flue gases. The power vents fan speed is variable depending on the rate of hot water used and the burner output. TO TURN OFF GAS TO APPLIANCE B Turn off the manual gas shut off on the supply line to the heater and set the ON/OFF switch to the OFF (0) position. Note: a manual gas shut off valve is not supplied with the heater. 20 6 720 607 072 Operation instructions 3 Operation instructions Fig. 27 1 2 3 4 5 6 On/Off switch Reset button Program Key Increasing temperature selector Decreasing temperature selector LCD display B Press buttons and requested temperature. in order to reach 3.1 On Power B To start the appliance switch the button to position (I). LCD display the default temperature - temperature factory setting 122°F (50°C). Fig. 29 If the outlet water temperature is set too high, the heater can produce temperatures that are too hot. A temperature balance shower valve can automatically mix in cold water to reduce such hot water temperature. In the event of any temperature instability with the use of a temperature balance shower valve, refer to shower valve manufacturer's instructions for internal adjustment setting. Adjustments should be made to the hottest setting in the shower valve. Additionally the temperature control of the heater can be lowered to produce a more comfortable hot water temperature. Fig. 28 Off B To shut down the appliance switch the button to position (0). 3.2 Temperature selection To select water temperature outlet: 6 720 607 072 21 Operation instructions Setting the water temperature The desired temperature of the hot water can be adjusted on the front control panel of the heater. The GWH-635-ES has an electronically controlled gas valve that modulates the burner input in response to both varying hot water flow rates and/or changes in any incoming and outgoing water temperatures. Hot Water Flow and Temperature with Various Inlet Temperature (gpm/Fahrenheit) 7.00 6.00 Hot Water Flow (GPM) 5.00 4.00 3.00 2.00 1.00 0.00 90 100 110 120 130 140 150 Hot water temperature (ºF) Inlet (ºF) 40 Inlet (ºF) 50 Inlet (ºF) 60 Inlet (ºF) 70 Hot Water Flow and Temperature with Various Inlet Temperature (lpm/Celsius) 24.00 20.00 16.00 12.00 8.00 4.00 0.00 35 40 45 50 55 60 65 Hot Water Flow (l/min) Hot water temperature (ºC) Inlet (ºC) 4 Inlet (ºC) 10 Inlet (ºC) 16 Inlet (ºC) 21 Programming the heater to display temperature readings in Celsius is possible, contact BBTNA for instruction. Fig. 30 Flow/temperature charts 22 6 720 607 072 Operation instructions 3.3 Use of remote control accessory Fig. 34 Reset button If the problem persists, contact your installer. Fig. 31 Remote control The wireless remote control accessory and the temperature selector buttons on the front of the water heater operate identically. Contact your distributor or BBTNA to order if the remote control accessory is preferred. Modification of the water heaters interior control unit (Fig. 29, component 12) is required when programming the remote control with this heater. 3.6 Program button Program button can be used/programmed in the appliance and in the remote control. Programming "Program" function Programming actions are similar for both controls (appliance control pad and wireless remote control). i 3.4 NOTE: up to 6 remote controls can be programmed for one single water heater, each with a range distance of 98 ft (30 m). Operation Fig. 35 "Program" key B Press buttons be memorized. and to select temperature to B When a hot water tap is opened, main burner ignites and LCD displays indication . B Hold "Program" button for 3 seconds to save temperature. Fig. 32 B LCD blinks until selected temperature is reached. When LCD stops blinking. Temperature is saved on "Program". Using "Program" function In order to select memorized temperature B Press "Program" key. consult LCD shows pre-memorized temperature, which is now the hot water selected temperature. 3.5 Reset button If the LCD shows the error symbol . See the error code on LCD and "Troubleshooting" section. 3.7 Locked condition This condition is only valid for appliances with more then 1 controller (appliances with remote control). Fig. 33 After following instructions "Troubleshooting" section indicated in Fig. 36 Locked condition Whenever LCD shows the temperature setting cannot be adjusted because the appliance is in use by a user which already selected a different temperature. Appliance will be automatically unlocked after closing hot water tap. B press reset button in order to make the appliance ready-to-work. 6 720 607 072 23 Maintenance and service 4 Maintenance and service Warning: Always turn off the electrical power supply, turn off the manual gas valve and turn off the manual water control valves whenever servicing. unit, the heater will communicate the source by these error codes. BURNERS DO NOT IGNITE WHEN HOT WATER IS TURNED ON · Cold incoming water connection made to wrong side of heater Make sure cold water inlet connection is plumbed to the right side of heater when facing unit · Water flow rate at hot water tap is too low A minimum of 0.8 gallon/minute (3 l/m) is required to activate the heater · Cold water inlet filter screen is dirty Remove water inlet filter screen and clean. The screen is located at the inlet connection to the water heater, disconnecting the main cold supply line at the heater is required. Check and clean faucet aerator screens too. · Crossover in plumbing The heater activates when there is sufficient water flow through its water valve, a minimum of 0.8 gallon/ minute (3 l/m) is required. If there is a crossover in the plumbing, the necessary hot water flow rate through the unit may not be reached, even though the flow at the hot water tap is sufficient. A plumbing crossover can be caused by a failed washer at a single lever faucet, incorrect plumbing or a faulty mixing valve in the piping. The crossover will create a back pressure on the water heater and prevent an adequate flow of water through it. To confirm there is no crossover in the plumbing, shut off the cold water supply feed to the water heater. Individually open each of the hot water taps. There should be no water flowing under a constant pressure. If there is a constant flow of water then the plumbing crossover must be corrected before the heater can operate properly. WATER IS TOO HOT · Temperature selection too high Lower temperature adjustment on heater or wireless remote control accessory, see chapter 3.2. WATER IS NOT HOT ENOUGH · Temperature selection too low Increase temperature adjustment on heater or wireless remote control accessory, see chapter 3.2 · Btu input is too low due to inadequate gas line sizing See specifications in chapter 2.10 - 2.12. The GWH-635-ES requires adequate gas pressure to reach desired temperatures, to compensate for inadequate gas supply or lack of gas pressure the GWH-635-ES will effectively reach the selected output temperature by reducing the hot water flow rate. Its motorized water valve makes this adjustment The unit should be checked once a year by a gas technician. If repairs are needed, the repairs should be done by a gas technician To remove front cover B Remove plastic decals on front panel (Page 5, Fig. 3). B Loosen the two Philips head screws located behind decals. B Lift front cover panel upward and remove. Systems and parts that should be checked at least once a year Reference diagrams on pages 29 and 30. · Venting system · Burners -see page 29 for observation window · Manual operation of the pressure relief valve to insure correct operation · Periodic cleaning of the water filter screen, see Fig. 25, chapter 2.13. · Flushing the heat exchanger with a descaling solution if mineral build up is evident. Scale build up will shorten the life of the water heater, descale heat exchanger thoroughly and repeat annually depending on mineral content of ground water. 5 Troubleshooting Introduction The GWH-635-ES burner is activated by a water flow valve. Numerous water related problems can cause this water valve to malfunction such as: Insufficient water flow volume to activate the burners at its minimum flow requirement; Dirt in the water flow valve causing it to malfunction; Sediment build-up in faucet aerators, or shower heads; Uneven pressures between cold and hot (with single lever mix valves); and Plumbing crossovers. These water flow related problems can cause the heater to deliver less than its full output, or to fail to ignite or to shut down completely. Problems stated below in upper case and in bold face should be investigated when there is a problem with the performance of the water heater but there is NO error code on the heater's LCD display or wireless remote control. Any failures that result in a displayed error code are referenced on page 26. A Functional Scheme of the GWH-635-ES is detailed on page 28. If there is a problem with the installation, venting or operation of the 24 6 720 607 072 Troubleshooting · Cold water is mixing with the hot water outlet (crossover) Test by following 4th bullet under BURNERS DO NOT IGNITE WHEN HOT WATER IS TURNED ON. LOW WATER FLOW/PRESSURE · Too many hot water applications are being used simultaneously or too much flow is being demanded The GWH-635-ES will effectively support two 2.02.5 gpm shower heads simultaneously or multiple sink applications. Greater draws will result in increased pressure drop and reduced flow at taps. See flow/temperature chart on page 22. · Btu input is too low due to inadequate gas line sizing See specifications in chapter 2.10 - 2.12. The GWH-635-ES requires adequate gas pressure to reach expected temperatures and flow rates, to compensate for inadequate gas supply or lack of gas pressure the GWH-635-ES will effectively reach the selected output temperature, but only by reducing the hot water flow rate. Its motorized water valve makes this adjustment. Proper gas pressure will need to be delivered before the motorized water valve will allow greater flow rates through it. Lowering the set temperature will also allow increased water flow rate through the motorized water valve. See flow/temperature chart on page 22. · Cold water inlet filter screen is dirty Remove water inlet filter screen and clean. The screen is located at the inlet connection to the water heater, disconnecting the main cold supply line at the heater is required. Check and clean faucet aerator screens too. HOT WATER TEMPERATURE FLUCTUATES / UNIT DEACTIVATED · Unbalanced pressure in water lines Any restriction caused by the water heater in the hot water system can result in uneven pressures between the cold and the hot. In such cases when mixing cold water at the tap (manually or automatically through a mix-type shower valve) the lower hot water pressure may be overpowered by the higher cold water pressure in the building and cause the hot water flow rate to fall below the minimum rate required. A pressure balance valve will help to resolve this symptom. · Temperature balance valves If the outlet water temperature is set too high, the heater can produce temperatures that are too hot. A temperature balance shower valve can automatically mix in cold water to reduce such hot water temperature. In the event of any temperature instability with the use of a temperature balance shower valve, refer to shower valve manufacturer's instructions for internal adjustment setting. Adjustments should be made to the hottest setting in the shower valve. Additionally the temperature control of the heater can be lowered to produce a more comfortable hot water temperature. · Inlet water pressure is erratic due to fluctuating supply water pressure For installation on a private well system with the use of a pressure tank, the lowest pressure range setting recommended is 30-50 psi (2.07-3.45 bar). The use of a pressure reducing valve after the pressure tank is also an effective way to maintain a constant water pressure to the water heater. Watts brand 25AUB¾" or N35B-¾" pressure relief valves or equivalent are suggested. NOISY BURNER / HEATER DURING OPERATION · CO2 range is out of adjustment. The cover must be in place to confirm CO2 readings. Operating with the cover removed may cause a noisy or unstable burner. See Chapter 9, CO2 adjustments can only be done by a certified gas technician with a calibrated CO2 analyzer. 6 720 607 072 25 Troubleshooting Display E9 EA Cause Temperature limiter opened circuit (overheat). Trips at 220F (104C). No ionization during safety time (safety time out). Note: appliance makes 3 ignition attempts before entering error mode "EA". The ionization signal momentarily disappeared more then 5 times in less then 30 seconds. Leakage error (gas valves do not close gas circuit). Ionization error (flame sensing at stand-by). Internal software/hardware failure. Hot water temperature sensor/receiver defect (from control unit). Solution Check connections.* Check heat exchanger condition.* Check gas pressure.* Check that gas is not diluted with air, as a result from recent gas pipeline rework.*. Check if vent terminal is blocked (especially when the appliance starts up for some seconds and then looses ionization signal).* Check ionization electrode.* Check for a proper ground.* Check gas valve and control unit.* Check control unit.* Check control unit.* Check water temperature sensor/receiver and connections.* Check room area temperature where heater is located, it must be above 36°F (2°C) Close water tap and allow 30 seconds for purging time. Open water tap and wait for 2 minutes to see if A9 message is deleted from the display. Check that the water temperature sensor/receiver is properly assembled in the water pipe.* Check that the water temperature sensor/receiver is in proper condition.* Check supply voltage.* Check fan and connections.* Check control unit.* Check if vent terminal is blocked or if vent terminal is according with chapter 2.9. * Check CO2 levels (see chapter 9).* Check supply voltage.* Check fan and connections.* Check control unit.* Check if vent terminal is according with EC FA F7 E0 A7 A9 Hot water temperature sensor/receiver misassembled (from control unit). Note: if display shows "A9" flashing, the appliance can be operated normally, but performance may be affected. C1 FAN rotation too low at start-up (from control unit). C6 FAN rotation too low at operation (from control unit). chapter 2.9.* C7 No rotational speed sensor signal from FAN Check fan and connections.* Check control unit.* Check CO2 levels (see chapter 9).* Check water valve and flow sensor.* Check water temperature sensor/receiver and connections.* Check room area temperature where heater is located, it must be above 36°F (2°C) Check connections to the overheat protection.* Check sensor continuity.* Check heat exchanger sealings and walls.* CA E2 Water flow signal over specified maximum value Inlet temperature sensor fault A2 Overheat protection fault Table 7 * By installer or service technician only. 26 6 720 607 072 Electrical diagram 6 Electrical diagram Fig. 37 Electrical scheme 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Intlet water temperature sensor Ionization sensor Water flow sensor Over heat protection Temperature limiter Gas valve Fan Water valve AC Plug Ignition electrode Display PCB ON/OFF switch Fuse T 2,5A Fuse T 3,15A Terminal block Ground post Outlet water temperature sensor 6 720 607 072 27 GWH-635-ES Functional scheme 7 GWH-635-ES Functional scheme Fig. 38 Functional scheme 28 6 720 607 072 Interior components diagram and parts list 8 8.1 Interior components diagram and parts list Interior components Fig. 39 Components 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Cover On/Off switch Reset button LCD display Program button Temperature switches Flue gas collector Mixer Heat exchanger Observation window Inlet air duct Control unit Exhaust fan Water valve Gas valve Fig. 40 Appliance overview 6 720 607 072 29 Interior components diagram and parts list 8.2 Components diagram 31 42 41 34 32 33 4 30 3 43 39 40 7 7 8 8 35 14 2 36 9 10 15 12 5 13 10 25 38 6 57 1 19 44 37 24 11 23 16 26 17 20