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  4. DIRECT VENTED GAS MODELS
  5. Installation And Operating Manual

A.O. Smith DIRECT VENTED GAS MODELS Installation And Operating Manual

Manual is about: RESIDENTIAL GAS WATER HEATERS

Summary of DIRECT VENTED GAS MODELS

  • Page 1

    1404 326940-001 residential gas water heaters installation and operating manual keep this manual in the pocket on heater for future reference whenever maintenance adjustment or service is required. Direct vented gas models not for use in manufactured (mobile) homes • for your safety • an odo rant is...

  • Page 2: Table of Contents

    2 www. Hotwater .Com table of contents safe installation, use and service . . . . . . . . . . . 3 general safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 quali fi ed installer or service agency . . . ...

  • Page 3

    Www. Hotwater .Com 3 safe installation, use and service your safety and the safety of others is extremely important in the installation, use and servicing of this water heater. Many safety-related messages and instructions have been provided in this manual and on your own water heater to warn you an...

  • Page 4: General Safety

    4 www. Hotwater .Com general safety read instruction manual before installing, using or servicing water heater. • do not store or use gasoline or other flammable vapors and liquids in the vicinity of this water heater, the vent termination hood or any other appliance. • avoid all ignition sources if...

  • Page 5: General Safety

    Www. Hotwater .Com 5 general safety breathing carbon monoxide can cause brain damage or death. Always read and understand instruction manual. • install vent system in accordance with codes. • do not operate water heater if flood damaged. • for operation above 7,700’, a high altitude orifice must be ...

  • Page 6: Introduction

    6 www. Hotwater .Com introduction thank you for purchasing this water heater. Properly installed and maintained, it should give you years of trouble free service. This water heater is suitable for potable water heating and space heating applications but not for space heating only applications. Abbre...

  • Page 7

    Www. Hotwater .Com 7 installation requirements for the commonwealth of massachusetts 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...

  • Page 8

    8 www. Hotwater .Com • if your water heater will be installed in the commonwealth of massachusetts, refer to the following graphic during installation and during modifications to the water supply system. In remove a must be vertical to ir bubbles e out coil air handler to air handler shut-off valve ...

  • Page 9: Typical Installation

    Www. Hotwater .Com 9 typical installation get to know your water heater - gas models (list referencing figures 1-5) 1 vent termination hood 2 wall plate 3 ***vent pipe 4 cold water inlet nipple/diptube 5 **combo heating system supply outlet (optional) 6 t&p valve 7 gas control valve/thermostat (hone...

  • Page 10

    10 www. Hotwater .Com natural gas and propane (lp) main burner with igniter assembly for 38k to 42k btu/hr models 31 36 38 39 30 33 34 35 32 37 40 figure 3 37 natural gas and propane (lp) main burner with igniter assembly for 47k btu/hr models 35 36 34 33 32 31 40 39 38 30 figure 4 vacuum relief val...

  • Page 11: Caution

    Www. Hotwater .Com 11 locating the new water heater facts to consider about the location carefully choose an indoor location for the new water heater because the placement is a very important consideration for the safety of the occupants in the building and for the most economical use of the applian...

  • Page 12: Warning

    12 www. Hotwater .Com air requirements for safe operation an adequate supply of fresh, uncontaminated air must be provided for combustion. This gas- fi red water heater is a direct vent model. It connects directly to the outside of the building through the vent termination hood. The hood operates as...

  • Page 13: Warning

    Www. Hotwater .Com 13 flammable do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. Storage or use of gasoline or other flammable vapors or liquids in the vicinity of this or any other appliance can result in serious injury or death. Can...

  • Page 14: Danger

    14 www. Hotwater .Com water piping water pressure the water supply pressure should not exceed 80 psi. If this occurs, a pressure reducing valve with a bypass should be installed in the cold water inlet line. This should be placed on the supply to the entire house in order to maintain equal hot and c...

  • Page 15

    Www. Hotwater .Com 15 installing the new water heater water piping installation note: water piping and vent piping occupy the space above the water heater. Plan the water piping to ensure it does not cause interference with the vent piping (see “venting”). • the system should be installed only with ...

  • Page 16: Caution

    16 www. Hotwater .Com a properly-sized and charged thermal expansion tank must be installed on all closed systems to control the harmful effects of thermal expansion. Contact a plumbing service agency or your retail supplier regarding the installation of a thermal expansion tank. Note: to protect ag...

  • Page 17: Caution

    Www. Hotwater .Com 17 the t&p valve must be manually operated at least once a year. Caution should be taken to ensure 1. No one is in front of or around the outlet of the discharge line, and 2. The water manually discharged will not cause any bodily injury or property damage because the water may be...

  • Page 18: Warning

    18 www. Hotwater .Com space heating and potable water systems this appliance has been design certi fi ed as complying with american national standard/csa standard for water heaters and are considered suitable for water (potable) heating and space heating. Note: this water heater may be used in combi...

  • Page 19

    Www. Hotwater .Com 19 combo heating this section serves as a guide for the installation and use of “combo” heating systems utilizing a domestic water heater that has been speci fi cally approved for such use. It is written for those knowledgeable in the required trades and professionals involved in ...

  • Page 20: Warning

    20 www. Hotwater .Com gas piping • do not use water heater with any gas other than the gas shown on the rating plate. • excessive pressure to gas control valve can cause serious injury or death. • turn off gas lines during installation. • contact qualified installer or service agency. Fire and explo...

  • Page 21: Warning

    Www. Hotwater .Com 21 certified gas supply flex pipe (properly sized for the heater input rate) sediment trap gas control valve ground joint union (optional) cap 3” min. Figure 13 black pipe sediment trap gas control valve ground joint union (optional) cap 3” min. Figure 14 sediment trap • contamina...

  • Page 22: Warning

    22 www. Hotwater .Com venting this direct vent water heater uses a sealed venting system to supply fresh combustion air to the heater and to exhaust the products of combustion ( fl ue gases) to the outdoors. The venting is a “pipe in a pipe” system. The inner (3”) piping carries out the exhaust fl u...

  • Page 23

    Www. Hotwater .Com 23 fresh combustion air in hot exhaust gas out screw figure 16 be sure venting is properly connected to prevent escape of dangerous flue gases which could cause deadly asphyxiation. Dv termination safety cover when the heater is in operation the vent termination hood will be hot (...

  • Page 24

    24 www. Hotwater .Com vent assembly the vent piping and the vent termination hood are to be connected as shown in figure 20. Maintain vent clearances to combustibles as shown in figure 21. Depending on your access to where the vent termination passes through the wall, you may wish to connect the pip...

  • Page 25

    Www. Hotwater .Com 25 inner corrugated pipe outer corrugated pipe restricter plate flue tube reducer apply silicone figure 23 vent connection to the water heater bend both the corrugated pipes toward the fl ue connection on the water heater. Pull and connect the inner corrugated pipe to the water he...

  • Page 26

    26 www. Hotwater .Com above anticipated snow level or 12” above grade a b low vent installation 7 6 8 1 c 5 1 9 figure 28 dim. 4038 5040 5047 a 80” max. B 9” min. C (recommended) 63.63” 73.00” 74.00” c (minimum) 60.75 69.50 70.50 d 14.25” min. Note: dimension “c” is the height above to fl oor to the...

  • Page 27

    Www. Hotwater .Com 27 installation checklist note: use and complete this checklist before lighting the heater. Correct any conditions that do not meet these instructions. Water heater location centrally located with the water piping system. Located as close to gas piping and vent pipe system as poss...

  • Page 28: Lighting Instructions

    28 www. Hotwater .Com lighting instructions 1. Turn the gas control/temperature knob counterclockwise to the "off" position. The status light will stop blinking and stay on for a short time after the water heater is turned off. See figure ‘a’. 329352-000 to turn off gas to appliance 1. Stop! It is i...

  • Page 29: Temperature Regulation

    Www. Hotwater .Com 29 temperature regulation temperature regulation temperature adjustment valves for reducing the point-of-use temperature by mixing cold and hot water are available (see figure 8). Also available are inexpensive devices that attach to faucets to limit hot water temperatures. Contac...

  • Page 30: For Your Information

    30 www. Hotwater .Com for your information external damage do not operate the water heater until it has been fully checked out by a quali fi ed technician, if the water heater: • has been exposed to fi re or damage. • displays evidence of sooting. • produces steam or unusually hot water. If the wate...

  • Page 31

    Www. Hotwater .Com 31 strange sounds possible noises due to expansion and contraction of some metal parts during periods of heat-up and cool-down do not necessarily represent harmful or dangerous conditions. Condensation causes sizzling and popping within the burner area during heating and cooling p...

  • Page 32: Maintenance

    32 www. Hotwater .Com maintenance for your safety and satisfactory operation, it is recommended that this heater be checked once a year by a competent service person. Users of this water heater should be aware that gas components wear out over a period of time. The gas carrying components of this wa...

  • Page 33

    Www. Hotwater .Com 33 burner flames inspect the burner flames through the viewport and compare them to the drawings in figure 32. A properly operating burner should produce a soft blue fl ame. Blue tips with yellow inner cones are satisfactory. The tips of the fl ame may have a slight yellow tint. T...

  • Page 34

    34 www. Hotwater .Com free the manifold tube and pilot tube. 7. Remove the screws (1/4” nut driver) securing the manifold/burner assembly to the combustion chamber (figure 34). 8. Carefully remove the manifold/burner assembly from the combustion chamber. Be sure not to damage any internal parts. Vie...

  • Page 35: Warning

    Www. Hotwater .Com 35 8. Using the pilot screw removed earlier, attach the new pilot/thermopile assembly. Reattach the burner to the manifold using the screws removed earlier. 9. Reinstall the manifold component block in the manifold door. Ensure that the pilot tube and wires are positioned as shown...

  • Page 36: Danger

    36 www. Hotwater .Com piezoelectric igniter system the piezoelectric igniter system consists of the igniter button, electrode, and wire. The pilot is ignited by an electric spark generated when the igniter button is pressed (see figure 39). Pilot/ thermopile bracket electrode thermopile pilot ignite...

  • Page 37

    Www. Hotwater .Com 37 to re fi ll the water heater storage tank 1. Close the water heater drain valve. 2. Remove the drain hose. 3. Open a nearby hot water faucet and leave open to allow air to escape. 4. Open the cold water inlet valve to the water heater. 5. To purge the lines of any excess air, k...

  • Page 38

    38 www. Hotwater .Com note: this rod may reduce but not eliminate water odo r problems. The water supply system may require special fi ltration equipment from a water conditioning company to successfully eliminate all water odo r problems. Arti fi cially softened water is exceedingly corrosive becau...

  • Page 39: Leakage Checkpoints

    Www. Hotwater .Com 39 leakage checkpoints service if a condition persists or you are uncertain about the operation of the water heater contact a service agency. Use this guide to check a “leaking” water heater (see figure 44). Many suspected “leakers” are not leaking tanks. Often the source of the w...

  • Page 40: Reference Parts Listing

    40 www. Hotwater .Com reference parts listing replacement parts may be ordered through your plumber or the local distributor. When ordering replacement parts, always have the following information ready: 1. Model, serial and product number 2. Type of gas 3. Item number 4. Parts description 1 vent te...

  • Page 41

    Www. Hotwater .Com 41 natural gas and propane (lp) main burner with igniter assembly for 38k to 42k btu/hr models 31 36 38 39 30 33 34 35 32 37 40 flare nut †† † figure 47 37 natural gas and propane (lp) main burner with igniter assembly for 47k btu/hr models 35 36 34 33 32 31 40 39 38 30 flare nut ...

  • Page 42: Troubleshooting Guidelines

    42 www. Hotwater .Com troubleshooting guidelines problem possible cause(s) correction burner will not ignite 1. Pilot not lit 2. Thermostat set too low 3. No gas 4. Dirt in the gas lines 5. Pilot line clogged 6. Main burner line clogged 7. Defective thermopile 8. Defective gas control/thermostat 1. ...

  • Page 43

    Www. Hotwater .Com 43 problem possible cause(s) correction insufficient hot water 1. Thermostat set too low 2. Sediment or lime in tank 3. Water heater too small 4. Wrong piping connections 5. Leaking faucets 6. Wasted hot water 7. Long runs of exposed piping 8. Hot water piping in outside wall 9. L...

  • Page 44: Troubleshooting Chart

    44 www. Hotwater .Com status light and diagnostic code troubleshooting chart led status problem corrective action 0 flashes (led not lit) pilot light is not lit or thermopile has not yet reached normal operating temperature. Turn gas control valve/thermostat knob to “off”. Wait 10 minutes, then atte...

  • Page 45

    Www. Hotwater .Com 45 led status problem corrective action 4 flashes the gas control valve’s temperature sensor has detected that the water temperature was too high. Once this condition occurs, the main burner and the pilot light will be shut off. Since the pilot light will be off, should this condi...

  • Page 46: Notes

    46 www. Hotwater .Com notes.

  • Page 47: Notes

    Www. Hotwater .Com 47 notes.

  • Page 48

    500 tennessee waltz parkway, ashland city, tn 37015 phone: 800-527-1953 • fax: 800-644-9306 www.Hotwater.Com.