Instruction Manual RESIDENTIAL GAS WATER HEATERS POWER VENT/POWER DIRECT VENT GAS MODELS WITH DIRECT SPARK IGNITION MODELS GDHE-50/GDHE-75 SERIES 130/131 Ashland City, TN 37015 www.hotwater.com • For Your Safety • AN ODORANT IS ADDED TO THE GAS USED BY THIS WATER HEATER. Thank you for buying this energy efficient water heater. We appreciate your confidence in our products. ALL TECHNICAL AND WARRANTY QUESTIONS: SHOULD BE DIRECTED TO THE LOCAL DEALER FROM WHOM THE WATER HEATER WAS PURCHASED.
TABLE OF CONTENTS SAFE INSTALLATION, USE AND SERVICE.................................3 Filling The Water Heater..........................................................23 APPROVALS..................................................................................3 INSTALLATION REQUIREMENTS FOR THE COMMONWEALTH GENERAL SAFETY INFORMATION..............................................4 OF MASSACHUSETTS................................................................24 Precautions..........................
SAFE INSTALLATION, USE AND SERVICE The proper installation, use and servicing of this water heater is extremely important to your safety and the safety of others. Many safety-related messages and instructions have been provided in this manual and on your own water heater to warn you and others of a potential injury hazard. Read and obey all safety messages and instructions throughout this manual.
GENERAL SAFETY INFORMATION PRECAUTIONS HYDROGEN GAS FLAMMABLE DO NOT USE THIS APPLIANCE IF ANY PART HAS BEEN EXPOSED TO FLOODING OR WATER DAMAGE. Immediately call a qualified service technician to inspect the water heater and to make a determination on what steps should be taken next. Explosion Hazard If the unit is exposed to the following, do not operate heater until all corrective steps have been made by a qualified service technician. Flammable hydrogen gases may be present. 1. External fire.
GENERAL SAFETY INFORMATION 5
GENERAL SAFETY INFORMATION Fire or Explosion Hazard Fire Hazard Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. For continued protection against risk of fire: Do not install water heater on carpeted floor. Do not operate water heater if exposed to flooding or water damage. Avoid all ignition sources if you smell gas. Do not expose water heater controls to excessive gas pressure. Use only the gas shown on the water heater rating plate.
INTRODUCTION Detailed installation diagrams are also found in this manual. These diagrams will serve to provide the installer with a reference. It is essential that all venting, water piping, gas piping and wiring be installed as shown. Thank You for purchasing this water heater. Properly installed and maintained, it should give you years of trouble free service.
DIMENSIONS AND CAPACITY DATA ROUGH IN DIMENSIONS: 50 GALLON UNIT Figure 1: DIMENSIONS FOR 50 GALLON UNIT ROUGH IN DIMENSIONS: 75 GALLON UNIT Figure 1A: DIMENSIONS FOR 75 GALLON UNIT Table 1 – ROUGH-IN-DIMENSIONS Units 50G 75G A B C D E F G H I Inches 66.75 49.25 22.00 15.75 3.00 8.00 8.00 62.00 65.00 cm 169.5 125.09 55.88 40.00 7.62 20.32 20.32 157.48 165.1 Inches 64.71 45.64 27.75 16.00 3.71 8.00 7.93 57.36 58.98 cm 164.4 115.9 70.5 40.6 9.4 20.3 20.1 145.
DIMENSIONS AND CAPACITY DATA Table 2 – CAPACITY, GAS AND ELECTRICAL CHARACTERISTICS Approximate Capacity *Manifold Pressure Electrical Characteristics U.S. Gals. Liters Gas Type “WC kPA Volts/Hz Amperes 50 189 Nat./LP 0 75 284 Nat/LP 0 0 120/60 <5 0 120/60 <5 * The manifold pressure is the factory setting and is not adjustable. A negative pressure will be seen with just the blower running without the Gas Control Valve open. All models - Maximum Supply Pressure: 14 inches W.C. (3.
FEATURES AND COMPONENTS 50 GALLON UNIT **29 20 23 21 22 **14 **15 5 1 12 18 21 16 25 11 ACCESS PANEL 17 24 33 18 35 Caution: This access panel covers 13 32 a 2” NPT plug that was required during the manufacturing of this water heater. This 2” NPT flange is not a cleanout fitting, removing the 2” NPT plug and using this fitting as a cleanout could void your warranty.
FEATURES AND COMPONENTS (CONT.) 75 GALLON UNIT **29 **14 20 21 5 18 21 23 22 **15 12 11 17 25 13 1 24 18 3 16 2 26, 27 31 4 35 33 19 32 34 30 VACUUM RELIEF VALVE 28 *INSTALL PER LOCAL CODES * CAUTION HARNESS HAS 120 VAC. IN OPERATION. ** See Venting Installation and Condensate Piping for more information.
FEATURES AND COMPONENTS (CONT.
CONTROLS AND SWITCHES close. The pressure switch is connected to the blower pressure tap by a piece of tygon tubing. This tubing must be connected in order for the switch to change the electrical contacts. The controller requires that the electrical contacts on this air flow switch be open before it will allow the blower to come on. This model is provided with three pressure switches. These switches are essential to the safe and proper operation of the unit. All switches are wired in series.
INSTALLATION CONSIDERATIONS LOCATING THE WATER HEATER (such as adhesives, etc.) emit flammable vapors which can be ignited by a gas water heater’s ignition device or main burner. The resulting flashback and fire can cause death or serious burns to anyone in the area. Carefully choose a location for the new water heater. The placement is a very important consideration for the safety of the occupants in the building and for the most economical use of the water heater.
mentioned below, see Figure 1B & Figure 1C). Failure to follow these instructions can restrict the air flow required for proper combustion, potentially resulting in fire, asphyxiation, serious personal injury or death. • Do not apply insulation to the top of the water heater, as this will interfere with safe operation of the blower assembly. • Do not cover the control system LCD on top of the water heater. • Do not cover the outer door, thermostat or temperature & pressure relief valve.
UNCONFINED SPACE FRESH AIR OPENINGS FOR CONFINED SPACES An Unconfined Space is one whose volume IS NOT LESS THAN 50 cubic feet per 1,000 Btu/hr (4.8 cubic meters per kW) of the total input rating of all appliances installed in the space. Rooms communicating directly with the space, in which the appliances are installed, through openings not furnished with doors, are considered a part of the unconfined space.
AIR FROM OTHER INDOOR SPACES Alternatively a single permanent opening, commencing within 12 inches (300 mm) of the top of the enclosure, shall be provided. See Figure 6. The water heater shall have clearances of at least 1 inch (25 mm) from the sides and back and 6 inches (150 mm) from the front of the appliance.
INSTALLATION REQUIREMENTS CHEMICAL VAPOR CORROSION Corrosion of the flueways and vent system may occur if air for combustion contains certain chemical vapors. Such corrosion may result in failure and risk of asphyxiation. Spray can propellants, cleaning solvents, refrigerator and air conditioning refrigerants, swimming pool chemicals, calcium and sodium chloride (water softener salt), waxes, and process chemicals are typical compounds which are potentially corrosive.
MIXING VALVES SEDIMENT TRAPS Water temperature over 125°F (52°C) can cause severe burns instantly resulting in severe injury or death. Children, the elderly and the physically or mentally disabled are at highest risk for scald injury. Feel water before bathing or showering. Temperature limiting devices such as mixing valves must be installed when required by codes and to ensure safe temperatures at fixtures.
GAS SUPPLY SYSTEMS 5. When installing multiple water heaters in the same gas supply system it is recommended that individual positive lock-up gas pressure regulators be installed at each unit. Low pressure building gas supply systems are defined as those systems that cannot under any circumstances exceed 14” W.C. (1/2 PSI Gauge). These systems do not require pressure regulation.
SPACE HEATING AND POTABLE WATER SYSTEM THERMAL EXPANSION Your water heater is equipped with inlet/outlet connections for use in space heating applications (see Figure 9). If this water heater is to be used to supply both space heating and potable (drinking) water, the instructions listed below must be followed: As water is heated, it expands (thermal expansion). In a closed system the volume of water will grow when it is heated.
TEMPERATURE-PRESSURE RELIEF VALVE T&P VALVE DISCHARGE PIPE REQUIREMENTS: • Shall not be smaller in size than the outlet pipe size of the valve, or have any reducing couplings or other restrictions. This water heater is provided with a properly rated/sized and certified combination Temperature-Pressure Relief Valve (T&P relief valve) by the manufacturer.
7. Condensate clean out cap must be on and tight when unit is in operation. THIS SIDE VIEW OF EXHAUST ELBOW AND ARROW INDICATE THE LOCATION OF THE PRESSURE PORT EXHAUST (VENT) ELBOW CONDENSATE DRAIN LINE CONNECTION HIGH ALTITUDE INSTALLATIONS DRAIN LINE TO TERMINATE NO MORE THAN 6 INCHES (15.2cm) ABOVE DRAIN CONDENSATE CLEANOUT CAP CONDENSATE DRAIN LINE - FIELD INSTALLED BUILDING DRAIN Figure 11 DO NOT remove the factory installed exhaust/condensate elbow for any reason, see Figure 11.
INSTALLATION REQUIREMENTS FOR THE COMMONWEALTH OF MASSACHUSETTS For all side wall terminated, horizontally vented power vent, direct vent, and power direct vent gas fueled water heaters installed in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting, including but not limited to decks and porch
VENTING INSTALLATION combustion air intake during severe cold weather. To prevent the recirculation of flue gases, maintain as much distance as possible between the combustion air intake and the exhaust vent terminal refer to Figure 16 and Figure 17 on Page 29 & Page 30 respectively. Approved vent and intake air pipe materials: PVC pipe materials: • DWV ASTM-D2665 or CSA B181.2 • Schedule 40, 80, 120 ASTM-D1785 or CSA B137.3 • SDR Series ASTM-2241 or CSA B137.
POLYPROPYLENE INSTALLATIONS Polypropylene vent systems do not use cement to connect the pipe and elbow sections but use a push together gasket seal method. Do not attempt to connect Polypropylene with sealant cement. All vent connections MUST be secured by the vent manufacturer’s joint connector. The installer must use a specific vent starter adapter at the flue connection. The adapter is supplied by the vent manufacturer to adapt to its vent system.
VENT PIPE TERMINATION INSTALLATION OF HORIZONTAL THROUGH THE WALL VENT SYSTEM The first step is to determine where the vent pipe will terminate. See Figures 12 through 20. The vent may terminate through a sidewall as shown in Figures 12, 14 and 15 or through the roof as shown in 18, 19 and 20. If you are installing your system so that it vents through roof, please refer to section titled VERTICAL VENT TERMINAL INSTALLATION. VENT TERMINAL INSTALLATION, SIDEWALL 1.
DIRECT VENT TERMINAL INSTALLATION B.) WOODEN SIDE WALLS Drill a pilot hole approximately one quarter inch outside of the marked circle. This pilot hole is used as a starting point for a saws-all or sabre saw blade. Cut around the marked circle staying approximately one quarter inch outside of the line. (This will allow the vent pipe to easily slide through the opening. The resulting gap will be covered by the vent terminal cover plates.
TERMINATION CLEARANCES SIDEWALL POWER VENT POWER VENT (using room air for combustion) EXTERIOR CLEARANCES FOR SIDEWALL VENT TERMINATION G V D H A v E L v B FI XE D CLOSED V F B B C OPERABLE V OPERABLE V B B FI XE D CLOSED M X V A V X V K J B V VENT TERMINAL X AIR SUPPLY INLET AREA WHERE TERMINAL IS NOT PERMITTED Figure 16 Vent terminal clearances for “Power Vent” installations. Power Vent configurations use room air for combustion.
TERMINATION CLEARANCES SIDEWALL DIRECT VENT DIRECT VENT (using outdoor air for combustion) EXTERIOR CLEARANCES FOR SIDEWALL VENT TERMINATION G V D H A v E L v B FI XE D CLOSED V F OPERABLE V B B C OPERABLE V B FI XE D CLOSED M X V B V X V K J A B V VENT TERMINAL X AIR SUPPLY INLET AREA WHERE TERMINAL IS NOT PERMITTED Figure 17 Vent terminal clearances for “Direct Vent” installations. Direct Vent configurations use outdoor air for combustion.
VERTICAL VENT TERMINAL INSTALLATION WHEN TERMINATING THROUGH A ROOF, THE FOLLOWING SPECIFICATIONS PERTAINING TO TERMINAL LOCATION MUST BE FOLLOWED. 1. Proper support must be provided for all pipe protruding through the roof. 2. The vertical roof terminations should be sealed with a plumbing roof boot or equivalent flashing. 3. The air intake termination and the exhaust vent termination must penetrate the same side of roof. 4.
DIRECT VENT DIAGRAM 12” MINIMUM CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL 12” MINIMUM CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL Figure 21 Figure 22 24” MINIMUM SEPARATION. EXHAUST MUST BE AT SAME LEVEL OR ABOVE INTAKE TERMINAL. SNORKELING IS ALLOWED TO ACHIEVE PROPER CLEARANCE. THE SNORKEL MUST BE SECURELY SUPPORTED.
CONCENTRIC VENT INSTALLATION INSTALLATION VERTICAL ROOF TERMINATION This water heater is certified for concentric venting with concentric vent kit #9006328005. Follow instructions below for proper installations. 1. Determine best location for termination kit. NOTE: Roof termination is preferred since it is less susceptible to damage, has reduced chances to intake contaminants, and less visible vent vapors. Table 8 – KIT COMPONENTS 2. Cut 1 hole (5 in. diameter) 3.
INSTALLATION SIDE WALL TERMINATION NOTE: Do not allow insulation or other materials to accumulate inside pipe assembly when installing through hole. 5. Secure assembly to roof structure as shown in Figure 28 using field supplied metal strapping or equivalent support material. NOTE: Ensure termination height is above the roof surface or anticipated snow level as shown in Figure 28. 6.
MULTI-CONCENTRIC VENT TERMINATIONS 6. Ensure the Y connection is oriented so the air intake side of Y is on top, see Figure 31. When two or more water heaters are direct vented with concentric vent terminations near each other, each water heater must be individually vented. NEVER common vent this water heater. When two or more water heaters are direct vented using concentric vent terminations, the water heaters may be vented as shown in Figure 32 and Figure 33. 7.
LOW PROFILE TERMINATION INSTALLATION This water heater is certified for sidewall direct venting with IPEX System 636 Low Profile Vent Kit. Follow instructions below for proper installations. To Boiler Intake Air Connection All termination kits must be located and installed in accordance with local codes or the current editions of the National Fuel Gas Code (ANSI Z223.1/NFPA 54). From Boiler Vent Pipe Connection 1.
LIGHTING AND OPERATION LABELS Set the “ENABLE/DISABLE” switch on the control panel to the “DISABLE” position. Operating Set Point: Status: Heating 130° F UP Wait five (5) minutes to clear out any gas. Then smell for gas, including near the floor. If you smell gas, STOP! Follow “B” in the safety information above on this label. If you don’t smell gas, go to the next step. OFF GAS O N Menu Help DN Set the “ENABLE/DISABLE” switch on the control panel to the “ENABLE” position.
TEMPERATURE REGULATION It is recommended that lower water temperatures be used to avoid the risk of scalding. It is further recommended, in all cases, that the water temperatures be set for the lowest temperature which satisfies your hot water needs. This will also provide the most energy efficient operation of the water heater. Valves for reducing the point-of-use temperature by mixing cold and hot water are available.
CONTROL SYSTEM OPERATION OVERVIEW • The water heaters covered in this manual are equipped with an electronic control system that regulates water temperature inside the storage tank. Heating cycles and ignition are managed by the control system. The ECO (energy cut out), Flame Sensor, pressure switches and Temperature Probe is monitored by the control system. The Combustion Blower, Igniter and the 24 Volt Gas Control Valve are all energized by the control system.
STATUS ICONS The Status Icons are displayed on the Desktop screen and convey operational and diagnostic information. The icons are described in the table below. Table 12 – STATUS ICONS Icon Description Water temperature in the tank has fallen. Shaded area of the animated thermometer icon will rise and fall in response to water temperature in the storage tank as sensed from the Temperature Probe. Water temperature in the tank has reached the Operating Set Point. The control system enters the Standby mode.
OPERATING STATES The current operational state of the water heater is displayed on the Desktop screen as the Status. The common operational states are described in the table below. Table 13 – OPERATING STATES State Standby Input Verification Description The water heater is not in an active heating cycle. IE: the Tank Temperature is at or above the Operating Set Point minus temperature differential. The control system is conducting a diagnostic check at the beginning of a heating cycle.
USER SETTINGS & CONTROL SYSTEM MENUS TEMPERATURES OPERATING SET POINT AND DIFFERENTIAL ADJUSTMENT The Operating Set Point is adjustable from 90°F (42°C) to 160°F (71°C). The factory setting is 120°F (49°C). The Differential is adjustable from 2° to 20°. The factory setting is 8°. These user settings are accessed from the Temperatures menu. These instructions explain how to adjust these settings and navigate the control system.
TEMPERATURES (CONT) DESCRIPTION/ACTION DISPLAY • Tank Probe Offset - adjustable user setting, range -5° to +5°F (factory setting 0°F). The Tank Probe Offset is used to calibrate control system temperature sensing. This offsets to more effectively read point of use temperature in the tank. This feature can also be used to compensate for building recirculation loops (hot water returning to the storage tank) that may cause the heating cycles to terminate prematurely.
DISPLAY SETTINGS DESCRIPTION/ACTION DISPLAY Select Display Settings from the Main Menu and press the Operational Button under "SELECT" to enter this menu. This menu contains adjustable display options for viewing information on the LCD screen. Use the Up & Down Buttons to navigate the menu. Display Settings • Temperature Units - Adjustable user setting that changes temperature units display to Celsius °C or Fahrenheit °F.
CURRENT FAULT DESCRIPTION/ACTION DISPLAY Select Current Fault from the Main Menu and press the Operational Button under "SELECT" to enter this menu. This menu contains non adjustable operational information. Use the Up & Down Buttons to navigate the menu. Blocked Exhaust Fault occurred 2 mins ago Restriction in exhaust pipe. Check exhaust pipe and termination for blockage. This menu contains the current Fault or Alert error message. The time the Fault or Alert message occurred appears directly below.
SERVICE CONTACT INFORMATION The control system has a discrete menu that Installing contractors and/or qualified service technician can access to enter contact information for their customers. This contact information will be displayed with all Fault and Alert messages. DESCRIPTION/ACTION DISPLAY From the Desktop Screen press and hold down the middle (unmarked) Operational Button for 30 seconds and then release it.
FOR YOUR INFORMATION START UP CONDITIONS the anode rod is one of a rotten egg smell in the hot water. The smell is a result of four factors which must all be present for the odor to develop: SMOKE/ODOR It is not uncommon to experience a small amount of smoke and odor during the initial start-up. This is due to burning off of oil from metal parts, and will disappear in a short while. a. A concentration of sulfate in the supply water. b. Little or no dissolved oxygen in the water. THERMAL EXPANSION c.
PERIODIC MAINTENANCE VENTING SYSTEM INSPECTION by protecting the glass-lined tank from corrosion. Adverse water quality, hotter water temperatures, high hot water usage, hydronic heating devices, and water softening methods can increase the rate of anode rod depletion. Once the anode rod is depleted, the tank will start to corrode, eventually developing a leak. Certain water conditions will cause a reaction between the anode rod and the water.
POWERED ANODE ROD (OPTIONAL MODELS) If the Temperature-Pressure Relief Valve on the water heater weeps or discharges periodically, this may be due to thermal expansion. To insure a long, trouble-free operating life, certain models of water heaters covered in this manual are factory equipped with a powered anode system. The anode rod is of a permanent design and does not need replacing unless damaged. Inspection and cleaning should be performed once a year.
TO DRAIN THE WATER HEATER STORAGE TANK: 7. Flush the water heater storage tank to remove sediment and allow the water to flow until it runs clean. 8. Close the water heater drain valve when flushing is completed. 9. Remove the drain hose. 10. Fill the water heater - see Filling The Water Heater in this manual. 11. Turn on the electrical supply to place the water heater back in operation. 12. Allow the water heater to complete several heating cycles to ensure it is operating properly. 1.
LEAKAGE CHECKPOINTS Never use this water heater unless it is completely filled with water. To prevent damage to the tank, the tank must be filled with water. Water must flow from the hot water faucet before turning “ON” gas to the water heater. B:Anode Rod Connection A:Inlet & Outlet A *Condensation may be seen on pipes in humid weather or pipe connections may be leaking. G:Recirculation Connection B. *The anode rod fitting may be leaking. C:T & P Connection C.
TROUBLESHOOTING INSTALLATION CHECKLIST Flow Chart. The list below represents some of the most critical installation requirements that, when overlooked, often result in operational problems, down time and needless parts replacement. This is not a complete list. Before performing any troubleshooting procedures use the list below to check for installation errors. Costs to correct installation errors are not covered under the limited warranty.
SEQUENCE OF OPERATION FLOW CHART If tank temperature drops below Operating Set Point minus Differential setting a heating cycle is activated Control System performs diagnostic checks Normal State of all pressure switches and ECO are checked Blower Prover pressure switch verified open All other pressure switches and ECO are verified closed NO Control System Locks Out Displays Fault Msg Combustion Blower is energized Pre-Purge cycle Blower Prover switch contacts confirmed closed by control system NO Ig
OPERATIONAL PROBLEMS If the Main Burner ignites momentarily but does not sustain ignition allow the water heater to try to ignite up to two more times until control system locks out and the Ignition Failure Fault message is displayed on the control system's LCD. If the water heater is experiencing rough starts see Rough Starting, Rough Operation on this page.
FAULT AND ALERT CONDITIONS are operational problems. This is not a complete list. Along with each of the Fault and Alert messages described there will be a list of possible causes and things to check and repair. FAULT CONDITIONS When the control system declares a Fault condition it will display a Fault message on the control system's LCD with an exclamation "!" mark. The control system will lock out and disable heating operation until the condition is corrected.
FAULT AND ALERT MESSAGES (CONT) Call the technical support phone number listed on the back cover for further technical assistance or to locate a qualified service technician in your area. POSSIBLE CAUSES - CHECK/REPAIR DISPLAYED FAULT/ALERT MESSAGE • Ensure excessive wind is not pressurizing the intake air or exhaust pipe. • Confirm wire connections of the blower prover switch are clean, tight, and not jumped/shorted. • Use multi-meter to check continuity/resistance of blower prover pressure switch.
WIRING DIAGRAM CAUTION LABEL ALL WIRES PRIOR TO DISCONNECTION WHEN SERVICING CONTROLS. WIRING ERRORS CAN CAUSE IMPROPER AND DANGEROUS OPERATION. VERIFY PROPER OPERATION AFTER SERVICING.
NOTES 58
LIMITED RESIDENTIAL GAS WARRANTY b. Shipping and delivery charges for forwarding the new water heater or replacement part from the nearest distributor and returning the claimed defective heater or part to such distributor except in the state of California where such charges are the manufacturer’s responsibility. c. All cost necessary or incidental for handling and administrative charges, and for any materials and/or permits required for installation of the replacement heater or part.
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