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- A.O. Smith
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- GCV Series
- Service Handbook
A.O. Smith GCV Series Service Handbook
Summary of GCV Series
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Models: gcv, gcvh, gcvl, gvr, xcv, xcvl, xgv, xvr - series 200/201 gvrl, xvrl (40-gallon short) series 202/203 06/09 316877-000 service handbook for standard residential fvir gas water heaters http://waterheatertimer.Org/how-to-troubleshoot-gas-water-heater.Html.
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3 your safety and the safety of others is extremely important in the servicing of this water heater. Many safety- related messages and instructions have been provided in this handbook and on your water heater to warn you and others of a potential hazard. Read and obey all safety messages and instruc...
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Fire or explosion harzard do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. Avoid all ignition sources if you smell natural or lp gas. Do not expose water heater control to excessive gas pressure. Use only gas shown on rating plate. Ma...
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Problem possible cause test / corrective action 5 troubleshooting quick reference no hot water: insuffi cient combustion air or venting issues – combustion chamber thermal cut off tripped. Follow the steps on pp 18 – 19. Always check and clean the base ring fi lter and the fl ame arrestor. Pilot wil...
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Problem possible cause test / corrective action 6 water leakage: thermostat does not shut-off check the gas control valve/thermostat as described on p. 20-21. Drain valve dripping/leaking back fl ush to clean- out sediment, replace if necessary tank leak check leakage checkpoints described on p. 25..
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7 table of contents basic installation ...................................................................................................................................... 8-16 draining and filling the water heater ......................................................................................
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8 exhaust vent to ouside of building union union water shut-off valve water supply- cold* expansion tank pressurize to equal supply water pressure* (relieve water pressure on the expansion tank before adjusting air pressure.) temperature-pressure relief valve with discharge piped to an adequate drai...
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9 this portion of this handbook applies to the operations and servicing of residential gas, tank type, water heaters, which are vented atmospherically and use a thermocouple as their electrical source. Control: there are two gas control valve/thermostat confi gurations available. Both valves have si...
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10 burner/manifold door assembly: the burner/manifold assembly consists of several components such as: main burner, burner orifi ce, manifold tube, pilot burner, pilot orifi ce, pilot tube, igniter, and thermocouple. See the fi gure below for the complete list of components. The pilot burner remains...
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11 energy cut off (eco): a metal tube (temperature probe) mounted onto the back of the gas control valve/thermostat is immersed inside the tank water. The probe acts as a temperature high limit. If water gets excessively hot, an energy cut off (eco) switch within the probe opens, interrupting the sm...
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12 thermostat operation: standard residential water heaters use mechanical thermostats. With a mechanical thermostat, a dial setting of 120° f may shut the burner down at a tank temperature between 110° and 130° f. The heater will consistently shut off at this same temperature. For this same reason,...
Page 13: Warning
13 basic installation & operation table 1: btuh input minimum square feet with 8’ ceiling typical room with 8’ ceiling 30,000 188 9 x 21 45,000 281 14 x 20 60,000 375 15 x 25 75,000 469 15 x 31 90,000 563 20 x 28 105,000 657 20 x 33 120,000 750 25 x 30 135,000 844 28 x 30 important: • the area must ...
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14 basic installation & operation all air from inside the building: when additional air is to be provided to the confi ned area from additional room(s) within the building, the total volume of the room(s) must be of suffi cient size to properly provide the necessary amount of fresh air to the water ...
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15 basic installation & operation vent connectors: 1. Type b, double wall, u.L. Listed vent pipe. 2. Single wall vent pipe. Maintain the manufacturer’s specifi ed minimum clearance from combustible materials when using type b double wall vent pipe. Vent connectors made of type b, double wall vent pi...
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16 • the connector must be firmly attached and sealed to prevent it from falling out. • to aid in removing the connector, a thimble or slip joint may be used. • the connector must not extend beyond the inner edge of the chimney as it may restrict the space between it and the opposite wall of the chi...
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17 draining and filling the water heater d raining the water heater the water heater should be drained if being shut down during freezing temperatures. Also, periodic draining and cleaning of sediment from the tank may be necessary. 1. Turn off the gas to the water heater at the manual gas shut-off ...
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18 checking the gas supply pressure checking the gas supply pressure gas pressure checks are done with flowing gas using a gas pressure gauge capable of reading pressure in inches of water column. • supply gas pressure checks are measured before the gas control valve/thermostat and as close to the w...
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19 checking for sufficient combustion air or venting issues flue products vented to ouside of building draft hood dilution air air is drawn in for combustion. Keep area clean and free from combustibles and flammable vapors. Dilution air (relief opening) dilution air match outer door draft test after...
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20 testing the thermocouple and gas control valve/thermostat thermocouple output test the following test will check the dc voltage generated by the thermocouple when the pilot light is lit. 1. Disconnect the thermocouple from the gas control valve/thermostat as shown in the adjacent figure. 2. Using...
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21 removing the burner from the manifold/ burner assembly natural gas (low nox) & l.P. Gas burner 1. Take off the burner by removing the two (2) screws located underneath the burner. 2. Check the burner to see if it is dirty or clogged. The burner may be cleaned with soap and hot water. Burner (bott...
Page 22: Warning
22 other fittings not shown for clarity igniter wire thermocouple two piece wire connector retainer clip pilot tube pilot bracket pilot manifold tube manifold/burner door opening ferrule nut figure 25 replacing the manifold/burner assembly warning explosion hazard • tighten both manifold door screws...
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23 manifold tube tip bracket slot close-up inside view of the combustion chamber. Figure 27 removing and replacing the gas control valve/thermostat important: this water heater has a resettable thermal switch installed. Do not attempt to disable or modify this feature in any way. Use only factory au...
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24 adjusting the temperature on the gas control valve thermostat water temperature over 125°f (52°c) can cause servere 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 o...
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25 gas water heater sizing guide use the following information as a guide to approximate the correct size water heater for the residence: 30 gallon size (21 gallon draw) for one bath residence. • 40 gallon size (28 gallon draw) for two bath residence -or one bath with an automatic clothes washer. • ...
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26 technical bulletins water hammer ..................................................................................................................................................27 mineral build-up .....................................................................................................
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27 bulletin 11 water hammer general water hammer is the destructive force, pounding noise and vibration in a piping system when water fl owing through a pipeline is stopped abruptly. When water hammer occurs, a high intensity pressure wave travels back through the piping system until it reaches a po...
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28 bulletin 13 mineral build-up symptoms • rumbling • crackling • popping cause with the increase in fuel costs and hot water consumption, deliming has become a necessity of modern maintenance. Lime (caco3), is the most notable factor when discussing water hardness. Lime is present in every water sy...
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29 bulletin 14 aluminum hydroxide symptoms “crackling”, “gurgling”, or “popping” noises from new water heaters (installed less than six months). Cause in a few isolated parts of the united states where the water supply has a relatively high ph (8+), water conditions will react with the aluminum anod...
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30 bulletin 15 condensation symptoms the water heater appears to be releasing water while the main burner is on or water is found surrounding the heater shortly after the water heater has been used. This bulletin explains why fl ue gases condense and how you can differentiate between condensation an...
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31 bulletin 21 discolored water symptoms rusty, brown, black, or yellow water appearing in the hot water. Causes complaints of discolored water are commonly blamed on water heaters and storage tanks, but in fact, it is a rare occurrence for today’s high quality glass lined tanks to have a lining fai...
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32 bulletin 22 smelly water causes the most common cause of “smelly water” is a non-toxic sulfate reducing bacteria, scientifi cally termed divibrio sulfurcans. This bacteria often enters the water system through construction or a break in ground piping. The bacteria creates the energy it needs to s...
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33 bulletin 23 chlorination procedure causes the chlorination procedure is used to eliminate various bacteria that accumulate and grow in water heaters. These bacteria often cause odorous or discolored water conditions. Procedure please read the steps of the chlorination procedure prior to beginning...
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34 bulletin 35 not enough hot water - gas causes complaints regarding an insuffi cient supply of hot water are typically the result of a water heater that cannot meet the demands of the residence (both people and appliances). The demand for suffi cient hot water may also be exceeded if additional pe...
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35 bulletin 45 thermal expansion symptoms • effects are only noticeable after hot water use followed by periods of no water use. • relief valve drips during any recovery cycle when no hot or cold water is used. • hot water pipes creak while heater is recovering and all valves are closed. • tanks or ...
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36 thermal expansion the fix the ideal fi x involves the use of a pressure reducing valve if supply pressures are above 60 to 70 psi, and a properly sized expansion tank. The prv reduces supply pressures to 40 to 60 psi allowing an economically priced and sized expansion tank to be used. The prv als...
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37 bulletin 52 leaking temperature and pressure relief valve symptoms • water seeping around the relief valve tank connection • leakage at the threaded portion of the relief valve connection • intermittent weeping and/or dribbling from the relief valve • large volume of hot water sporadically discha...
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38 bulletin 60 insulation blankets general the purpose of an insulation blanket is to reduce the standby heat loss encountered with storage tank heaters. Most modern water heaters have adequate factory installed insulation, the use of an after market insulation blanket is no longer recommended by mo...
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39 draw efficiency is the quantity of hot water available to the consumer before the outlet water temperature decreases 25 degrees f. A 40 gallon water heater will typically provide 70% (28 gallons) of this “usable” hot water (60% is the minimum). The burner or elements are allowed to operate during...
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40 one pound of gas pressure is equal to 27.7 inches water column pressure inches of water column x .036091 = psi inches of water column x .073483 = inches of mercury (hg.) centimeters = inches x 2.54 mm (millimeters) =inches x 25.4 meters = inches x .0254 doubling the diameter of a pipe will increa...
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41 notes.
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42 notes.
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44 all technical and warranty questions should be directed to the local dealer from whom the water heater was purchased. If you are unsuccessful, contact a o smith water heaters residential technical assistance at 1-800-527-1953 or www.Hotwater.Com..