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COMMERCIAL GAS WATER HEATERS

 

 

 

 

For additional information contact:

 

A. O. Smith Corporation

500 Tennessee Waltz Parkway
Ashland City, TN 37015

Tech Support: 800-527-1953
Parts: 800-433-2545
www.hotwater.com

Copyright © 2016 A. O. Smith Water Heater Company, All rights reserved.

Summary of Contents for BTR 120-400

Page 1: ...6 100277701_2000536453_Rev A 500 Tennessee Waltz Parkway Ashland City TN 37015 FOR MODELS BTR 120 thru 400 A Series 118 119 INSTALLATION CONSIDERATIONS PRE SERVICE CHECKS CONSTRUCTION OPERATION SERVIC...

Page 2: ...ATION FLOW CHART 13 FAULT AND WARNING CODES 14 Ignition Module 14 Flue Damper 14 Diagnostics Codes Ignition Module BTR 118 119 Series 15 TROUBLESHOOTING CHECKLIST 17 GENERAL SERVICE CHART 18 FAULT AND...

Page 3: ...ied as defined by ANSI above and licensed or certified as required by the authority having jurisdiction to perform a given task do not attempt to perform any of the procedures described in this servic...

Page 4: ...al expansion can cause premature tank failure leakage This type of failure is not covered under the limited warranty Thermal expansion can also cause intermittent Temperature Pressure Relief Valve ope...

Page 5: ...he National Fuel Gas Code ANSI Z223 1 and with the Category I Venting Tables If any part of the vent system is exposed to ambient temperatures below 40 F it must be insulated to prevent condensation D...

Page 6: ...ith power vent kits for sidewall venting A O Smith offers power vent kits for use on installations with a maximum of 100 equivalent feet of vent piping The power vent kits also use type B vent materia...

Page 7: ...W C for natural gas and 11 0 W C for propane gas The minimum supply pressure is measured while gas is flowing dynamic pressure The supply pressure should never fall below 4 5 W C for natural gas and...

Page 8: ...as lines or emergency malfunction of the supply system the gas valve must be checked for safe operation Make sure that the outside vents on the supply regulators and the safety vent valves are protect...

Page 9: ...eak test before placing the water heater in operation Disconnect gas piping and main gas shutoff valve before leak testing Install sediment trap in accordance with NFPA 54 Use joint compound or Teflon...

Page 10: ...its are equipped with an automatic flue damper that reduces heat loss during the OFF cycles The automatic flue damper drive assembly is a field replaceable part and may be obtained by contacting A O S...

Page 11: ...witch must be in the ON position to perform ohm continuity tests ON OFF switch replaced the gas cock on this new valve design GAS PRESSURE SPECIFICATIONS MODELS NATURAL BTR 120 400 PROPANE BTR 120 400...

Page 12: ...tic controls would allow the gas control valve to remain open causing water temperature to exceed the thermostat setting The water temperature would continue to rise until high limit switch operation...

Page 13: ...g checklist should be examined to eliminate obvious problems from those requiring replacement or servicing Check that main manual gas shut off valve is fully open and that gas service has not been int...

Page 14: ...13 Servicing should only be performed by a Qualified Service Technician SEQUENCE OF OPERATION FLOW CHART...

Page 15: ...Condensation on outside of tank normal Rumbling Sediment accumulation on bottom of tank Drain a quantity of water through drain valve If rumbling persists call a qualified service agency Delime heate...

Page 16: ...ANSION TANK FAULTY VALVE REPLACE RELIEF VALVE LARGE VOLUME WATER RELIEF FROM T P VALVE EXCESSIVE WATER TEMPERATURE CHECK WIRING REPLACE DUAL CONTROLLER FAULTY RELIEF VALVE REPLACE RELIEF VALVE PREMATU...

Page 17: ...VAC is supplied to the heater Make sure the tank is full of water Make sure the gas is supplied to the unit EFFIKAL DAMPER The wiring colors from the damper PC Board are different colors than the wire...

Page 18: ...r 3 Yellow White 24V Common 4 Black CONDITION Damper closed High Limit closed FLUE DAMPER Do not turn damper open manually or motor damage will result use the service switch All readings are taken fro...

Page 19: ...customer to have automatic heat until a replacement damper can be installed C DAMPER ROTATES CONTINUOUSLY Change the entire damper assembly D DAMPER STICKS 1 Make sure no screws obstruct the damper b...

Page 20: ...AC is not present Check Wiring Harness to Thermostat 24VAC present Damper Opens Continue to Step 3 CONDITION Damper rotates continuously STEP 3 TEST THE THREE AMP FUSE CONDITION Test via the terminals...

Page 21: ...s lights are not visible on the thermostat 24VAC out of the thermostat via the Yellow wire to ground is not present No Pilot or Main burner flame present Error indication LED light on the Honeywell mo...

Page 22: ...TEP 5 WIRE HARNESS TEST CONDITION Damper Open no 24VAC to module 24VAC terminal Test for 24 VAC between terminal 24V on the IID module and 24V GND IF THEN 24VAC is present This is correct Continue to...

Page 23: ...OT VALVE CONDITION 24VAC to module no pilot Using a multimeter test for 24 VAC between terminal PV and 24 V GND on the IID during the 90 second trial for ignition IF THEN The meter does not read 24 VA...

Page 24: ...k for spark at the pilot assembly Note The pilot burner mounts on the left side of the main burner IF THEN The igniter is not sparking during the 90 second trial for ignition Check for A 7 64 spark ga...

Page 25: ...ignal becomes a DC current that the module can interpret The pilot hood must be properly grounded and the pilot flame must remain in contact with both surfaces for the flame proving signal to remain c...

Page 26: ...EST CONDITION Pilot Flame Noted No Sparking No Main Burner Using a multimeter test for 24 VAC between terminal MV on the IID and 24V GND IF THEN 24 VAC is not present Replace the IID module Check the...

Page 27: ...chnician STEP 10 MAIN BURNER TEST CONDITION Pilot flame Noted Main burner Check Visually check for main burner IF THEN The main burner ignites Sequence is complete The main burner does not ignite Chec...

Page 28: ...27 Servicing should only be performed by a Qualified Service Technician WIRING DIAGRAM BTR 118 119 SERIES...

Page 29: ...28 Servicing should only be performed by a Qualified Service Technician WIRING DIAGRAM BTR 118 119 SERIES CONTROLS...

Page 30: ...29 Servicing should only be performed by a Qualified Service Technician NOTES...

Page 31: ...additional information contact A O Smith Corporation 500 Tennessee Waltz Parkway Ashland City TN 37015 Tech Support 800 527 1953 Parts 800 433 2545 www hotwater com Copyright 2016 A O Smith Water Hea...

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