A.O. Smith T-D2-IN Page 78 Service Manual Download

Page: 78 / 78

T-D2-IN / T-D2-OS Service Manual

Ver. 1.00

CONFIDENTIAL

15. Revisions

Version Description of changes

Date

1.00

First edition

11/01/10

Summary of Contents for T-D2-IN

Page 1: ...Service Manual Ver 1 00 1 CONFIDENTIAL T D2 IN T D2 OS On Demand Water Heater Service Manual T D2 IN A O Smith Water Products Company 500 Tennessee Waltz Parkway Ashland City TN 37015 Toll Free 1 877...

Page 2: ...ts in the interior view 8 5 Schematic diagram 10 6 Wiring diagram 11 7 Wiring diagram checkpoints for diagnosis 12 8 Resistance values of the temperature thermistors 14 9 Operational flow chart 15 10...

Page 3: ...Flow rate 0 75 to 10 0 GPM Available set temperatures 99 to 185 F default 122 F Temperature dipswitch settings 104 F 113 F 122 F 131 F 140 F 158 F 176 F 185 F Bypass valve Yes Thermistors 3 thermisto...

Page 4: ...m 120V AC 1 3 8 36 mm COLD 3 1 4 84mm 13 1 8 334mm 4 3 8 1 13 m m 5 1 8 130mm T D2 IN 1 3 3 4 35 0m m 1 0 2 5 4m m 1 3 4 4 5 mm 1 3 4 4 5 mm 1 3 8 36 mm 3 9 8 1 0 1m m 2 1 3 8 5 4 4m m 2 0 1 4 5 2 0m...

Page 5: ...mm HOT 5 1 4 133mm 120V 1 3 8 36mm GAS 4 7 8 124mm COLD 3 1 4 84mm 4 3 8 113mm 1 9 3 8 49 3 mm COLD 2 7 8 71mm 1 26mm HOT 6 1 2 164mm 9 1 2 241mm 120VAC 3 7 8 99mm GAS 5 1 4 135mm 1 5 8 4 3 mm 5 128mm...

Page 6: ...T D2 IN T D2 OS Service Manual Ver 1 00 6 CONFIDENTIAL 3 Interior view T D2 IN 1 3 4 5 6 7 9 8 31 10 11 13 14 15 16 17 18 18 19 2 21 12 23 24 32 25 22 28 29 27 30 20 26...

Page 7: ...T D2 IN T D2 OS Service Manual Ver 1 00 7 CONFIDENTIAL T D2 OS 1 3 4 5 6 7 9 8 31 10 11 13 14 15 16 17 18 18 19 2 21 12 23 24 32 25 22 28 29 27 30 2 0 26...

Page 8: ...Water inlet 404 EKK1U T K3 T K3 Pro T K3 SP OS T KJr2 IN OS T K4 IN OS 7 Water outlet 409 EKK1V T K3 T K3 Pro T K3 SP OS T KJr2 IN OS T K4 IN OS 8 Inlet thermistor 407 EKK38 T K3 T K3 Pro T H2 DV OS...

Page 9: ...SP OS T KJr2 IN OS T K4 IN OS T M50 22 Air fuel ratio rod AFR rod 108 EKK0E T K3 T K3 Pro T K3 SP OS T H2 DV OS T M50 T M32 23 Flame rod 108 EKK0E T K3 T K3 Pro T K3 SP OS T H2 DV OS T M50 T M32 24 Ig...

Page 10: ...the burner chamber 6 Water circulates through the heat exchanger and is heated up to the set temperature 7 Using thermistors to measure temperatures the computer modulates the gas and water valves to...

Page 11: ...n Y Yellow O Orange BR Brown BK W R B K W R W R R Flow Sensor W Bypass Valve Flame rod Ground AFR rod Y G O Inlet thermistor Output thermistor Mixing thermistor Remote controller Pump connectors Paren...

Page 12: ...ring operation 0 9 to 1 3 k Green blue at COM SV1 78 to 100 VDC during operation 1 3 to 1 9 k Orange blue at COM SV2 78 to 100 VDC during operation 1 3 to 1 9 k Red blue at COM SV3 78 to 100 VDC durin...

Page 13: ...hite Black 1 to 4 VDC pulse 1 080 pulse min more than 18 Hz I Air fuel ratio rod Yellow AFR rod Between AFR rod and the computer board More than 0 5 A during operation Flame rod Orange Flame rod Betwe...

Page 14: ...76 19 08 15 43 12 56 10 28 8 47 7 02 5 85 4 90 4 12 Temperature F 122 131 140 149 158 167 176 185 194 203 212 C 50 55 60 65 70 75 80 85 90 95 100 Resistance k 3 49 2 96 2 53 2 16 1 86 1 60 1 39 1 21 1...

Page 15: ...tor fault MV OFF SV2 OFF GPV OFF SV1 SV3 OFF Fan motor stop operation Faucet closes Flow sensor OFF Remove cause Opeartion lamp OFF Operation stop YES NO YES NO NO YES YES NO 20sec later YES NO NO YES...

Page 16: ...20 10 5 Flame rod 21 10 6 AFR rod 22 10 7 Heat exchanger 23 10 8 Flow adjustment valve 24 10 9 Flow sensor 25 10 10 Bypass valve 26 10 11 Thermistors 27 10 12 Hi limit switch 28 10 13 Overheat cutoff...

Page 17: ...2 Dust or soot deposit on the burner surface 3 Cracks on the burners 4 Gas leakage from the burners Effects on the water heater if burners fails 1 Unexpected combustion 2 Unstable flame conditions an...

Page 18: ...an cause poor combustion in the combustion chamber In this case the AFR rod will detect an improper flame condition and computer will take safety measures 2 Gas leakage from the manifold Error codes w...

Page 19: ...re to ignite or abnormal ignition 3 Unstable combustion conditions Error codes when the fan motor fails 101 111 121 611 991 Diagnostic 1 Visual inspection connection breakage of wires or dust causing...

Page 20: ...ection breakage of wires 2 Listen for clunk sounds from the gas valves opening right after fan motor initiates 3 Check voltages and resistance of coils proper range of values shown below Color Number...

Page 21: ...21 error code s will display 2 The water heater will not initiate the ignition process The 721 error code will display Error codes when the flame rod fails 111 121 721 Diagnostic 1 Visual inspection c...

Page 22: ...r heater will not initiate the ignition process The 721 error code will display 2 The fan motor speed cannot be modulated properly under abnormal flame conditions which can result in excessive CO emis...

Page 23: ...etect this event and immediately stop the water heater from operating 3 Abnormal sounds during combustion Error codes when the heat exchanger fails N A Diagnostic 1 Visual inspection soot deposits cra...

Page 24: ...sy Link system the 651 error code can occur Error codes when flow adjustment valve fails 651 only within Easy Link systems Diagnostic 1 Visual inspection connection breakage of wires motor drive locke...

Page 25: ...flow sensor fails 441 only within Easy Link systems Diagnostic 1 Visual inspection connection breakage of wires and or debris on impeller 2 Check voltages proper range of values shown below Color Numb...

Page 26: ...rly Effects on the water heater if bypass valve fails 1 Water leakage from failed valve can damage other water heater components 2 Temperature fluctuations in the hot water output Error codes when byp...

Page 27: ...heater will have temperature fluctuations in hot water Error codes when thermistors fails 311 Output 321 Inlet 331 Mixing Diagnostic 1 Visual inspection connection breakage of wires and or debris on t...

Page 28: ...he heat exchanger exceeds 194 F 90 C Note The mixing and output thermistors always act as backup hi limit detectors to detect excessively high water temperatures in the heat exchanger 2 The water heat...

Page 29: ...tantly The 111 or 121 error code will display Failure events 1 Unable to detect the excessively high temperatures within the water heater Effects on the water heater if the overheat cutoff fuse fails...

Page 30: ...tained in the heat exchanger to freeze up possibly causing the heat exchanger to burst Error codes when heaters fails N A Diagnostic 1 Visual inspection connection breakage of wires and the condition...

Page 31: ...computer board fails A component s may not operate within the water heater In most cases of computer board failure the whole the water heater does not operate at all Error codes will display Error co...

Page 32: ...er heater if transformer fails 1 The water heater does not operate due to lack of power from transformer 2 A failed transformer can cause electrical damage to other electrical components within the wa...

Page 33: ...er cannot ignite during the ignition process and the 111 or 121 error codes will display 2 No effects on the water heater however the durability of the igniter wears down Error codes when Igniter fail...

Page 34: ...tection thermostat fails 1 The freeze protection heaters will always be ON causing heat damage to components inside the water heater 2 The freeze protection heaters will never be able to turn on even...

Page 35: ...ure of the absorber Effects on the water heater if the fuse box fails 1 Unable to protect the computer board if high voltage gets applied to the unit The computer board can short out stopping all oper...

Page 36: ...F 6 Disconnection short circuit grounding of remote wires Normal 11 to 25 VDC between white black 7 Fault of PCB of remote control 1 Check for normal voltage at terminal It takes long time to get hot...

Page 37: ...s out of the flue Abnormal sound from water heater 1 Check the gas type of the water heater 2 Check how long the water heater has been installed and in use 3 Check the installation place 4 Check the a...

Page 38: ...low adjustment valve fault Normal 0 09 to 0 2 k between red black J Error Code Malfunction description Cancellation method 031 Incorrect dipswitch setting fault Turn off the power or water supply Diag...

Page 39: ...and or observed weak spark 1 Cracks soot on igniter rod 2 Improper gap between burner igniter rod Normal gap 0 16 4mm 3 PCB fault Normal 90 to 110 VAC at 7 purple purple during ignition B 3 PCB fault...

Page 40: ...During operation more than 1 A through the flame rod wire orange I 8 Check if hi limit switch is properly functioning Error Code Malfunction description Cancellation method 121 Error code is shown aft...

Page 41: ...1 Output thermistor fault Refer to section 10 11 Visual inspection connection breakage of wires and or debris on thermistor Check voltage resistance between black black 12 Refer to Section 8 for prope...

Page 42: ...description Cancellation method 510 Fault of driving circuit for main gas solenoid valve MV SV1 SV2 and or SV3 Turn off the power supply The computer checks the condition of the main gas valve immedi...

Page 43: ...the water heater using the diagnostics mode of the TM RE30 temperature remote controller See the 12 1 How to diagnose the water heater using the TM RE30 Visual inspection of PCB connection breakage of...

Page 44: ...the gas proportional valve Normal 20 to 40 between white red H1 Error Code Malfunction description Cancellation method 721 False flame detection Turn off the power or water supply Diagnosis Checkpoin...

Page 45: ...tion 12 3 Turn off the power or water supply If not possible press and hold the INC and DEC buttons on the computer board simultaneously for more than 3 sec Diagnosis Checkpoint 1 Check the gas type o...

Page 46: ...e Easy link system 55 12 7 A ON OFF conditions Overview 56 12 7 B ON OFF conditions BTU requirements 57 12 8 A Pump control ON OFF conditions Only for single and Easy link system 58 12 8 B Pump contro...

Page 47: ...g the HOT or COLD buttons Fig 1 shows mode 5 being selected When selecting information please refer to the table on p 49 for the proper mode 3 Press the INFO button to select the mode and the informat...

Page 48: ...sy link system of T D2 IN or T D2 OS a maximum of four units of the T D2 IN or T D2 OS s can be linked together 4 Press the INFO button to select the desired unit 5 When the desired unit is selected a...

Page 49: ...After 720 the next rotation occurs Air Fuel ratio rod current 0 to 999 0 1 A 8 ON OFF cycles during current rotation 0 to 100 cycles After 100 the next rotation occurs Flow rate 0 to 999 0 1 GPM 9 N A...

Page 50: ...ght in a circular 0 pattern one segment at a time Displaying error code history 1 Briefly press the Error call button do not hold down the button 2 If the T D2 IN or T D2 OS has had prior error codes...

Page 51: ...r sticking Vent Flaps installed on the Terminator Snow build up around Terminator Installed in a closet No Ventilation or lack of combustion air 6 If installed in laundry room check the burner and hea...

Page 52: ...ed If the AFR value is lower than the normal value the FM speed is decreased These values are read with the front cover close Measure the values after burning the water heater for ten minutes The AFR...

Page 53: ...ttings The functions of the upper bank of dipswitches No Functions ON position OFF position 1 Gas type Propane Disable 2 Natural gas Disable 3 Allow adjustments of fan motor speed Changing the FM spee...

Page 54: ...lt 2 Model type Default T D2 IN Disable 3 Default T D2 OS Disable 4 5 6 Output temperature settings See table to the right Default 122 F OFF ON 1 2 3 4 5 6 OFF ON 1 2 3 4 5 6 OFF ON 1 2 3 4 5 6 OFF ON...

Page 55: ...mputer board of all child units for at least 5 seconds 2 The 7 seg LED on the computer board of all child units will display 0 to signify that the computer memory has been erased of its previously ass...

Page 56: ...ter ON OFF Conditions Conditions needed to turn ON The BTU requirement is more than 14 880 BTU h AND The water flow rate is more than 0 75 GPM Conditions needed to turn OFF The BTU requirement is less...

Page 57: ...t that moment will be 120 F C ON OFF table Set temperature F Flow rate GPM 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 113 ON 53 5 83 2 93 2 98 1 101 1 103 1 104 5 105 6 OFF 65 4 89 2 97 1 101 1 103 5 105 1 106 2...

Page 58: ...ump to be controlled by the following conditions ON OFF Conditions Re circulation mode Conditions that activate the pump The BTU requirement is more than 18 600 BTU h OR 30 minutes have elapsed after...

Page 59: ...e pump OFF 122 Tin 2 5 500 14 800 Tin 107 1 F C ON OFF table Set temperature F Flow rate GPM 0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 113 ON 38 6 75 8 88 2 94 4 98 1 100 6 102 4 103 7 OFF 53 8 83 4 93 3 98 2 1...

Page 60: ...C GPM L min 100 122 37 50 3 4 13 131 55 3 2 12 140 60 2 9 11 149 65 2 6 10 158 167 70 75 2 4 9 176 185 80 85 2 1 8 2 Condition required to reduce the number of activated T D2 IN or T D2 OS A In the ca...

Page 61: ...t Left bank of dipswitches No 4 OFF No 5 OFF 1 2 000 to 4 000ft FM function the fan motor speed increased by 6 T D2 IN the fan motor speed increased by 4 T D2 OS Left bank of dipswitches No 4 ON No 5...

Page 62: ...ue through the coil will not exceed 1 amp For example To the right there is a sample of relay specifications from an arbitrary brochure You can select either the 120 VAC or 240 VAC relay because their...

Page 63: ...therwise proceed onto the next step 5 Press and hold down the MAX button on the computer board While holding down the MAX button press either the Increase or Decrease button to increase or decrease th...

Page 64: ...IAL 6 After gas pressure has been set deactivate the T D2 IN or T D2 OS remove the manometer tube and replace the port screw Computer board Figure 3 MAX button MIN button Increase button Decrease butt...

Page 65: ...tton on the computer board While holding down the MAX button press either the Increase or Decrease button to increase or decrease the fan motor speed respectively Figure 2 Refer to the remote controll...

Page 66: ...ng as each particular feature s activation requirements are met it is possible for both features to operate at the same time Automatic firing system Activation conditions will depend on the on whether...

Page 67: ...ly check the temperatures of the inlet and output thermistors The automatic firing system will not activate at all unless these 25 minutes have elapsed When the computer checks for these temperatures...

Page 68: ...mostat is located on the fan motor close in vicinity to the inlet and outlet pipes within the T D2 IN or T D2 OS Electrical power is required for this feature to operate The heating blocks will activa...

Page 69: ...off valve 5 Open all hot water taps in the house When the all water flow has ceased close all hot water taps 6 Have a bucket or pan to catch the water from the drain plugs of the T D2 IN or T D2 OS Un...

Page 70: ...Ver 1 00 70 CONFIDENTIAL 13 Components diagrams Case assembly T D2 IN T D2 OS 004 001 0 02 0 50 702 052 0 07 704 006 005 053 066 053 052 052 056 05 2 004 0 01 0 52 0 03 0 02 0 50 702 052 0 07 704 006...

Page 71: ...er control section Burner assembly Manifold assembly 116 117 053 103 054 115 057 058 713 106 107 108 109 110 065 712 121 703 053 706 70 4 70 5 120 053 711 053 714 062 055 053 117 401 059 060 103 401 1...

Page 72: ...09 455 410 454 408 064 403 4 62 458 4 60 4 56 454 411 45 9 053 153 154 152 463 413 452 450 4 53 451 414 B C C B 401 41 4 412 063 401 T D2 IN OS Exhaust section OS model Water outlet section Water inle...

Page 73: ...box inner plate T K3 T K3 Pro T K3 SP OS T H2 DV OS T KJr2 IN OS T K4 IN OS 007 EKK5H Back guard panel T K3 T K3 Pro T K3 SP OS T K4 IN OS 050 EW000 Screw M4 12 W Washer 051 EW001 Screw M4 10 w washer...

Page 74: ...K4 IN OS 106 EKK2V Burner window T K3 T K3 Pro T K3 SP OS T H2 DV OS T KJr2 IN OS T K4 IN OS T M50 T M32 107 EKK2W Rod holder gasket T H2 DV OS T KJr2 IN OS T K4 IN OS T M50 T M32 108 EKK0E Flame rod...

Page 75: ...O ring P20 NBR Black T K3 T K3 Pro T K3 SP OS T H2 DV OS T KJr2 IN OS T K4 IN OS T M50 152 EKK3G Silicon ring T K3 OS T K4 OS T M50 153 EKK53 Rain protection plate in Exhaust chamber T K3 SP OS T KJr...

Page 76: ...451 EK031 Heater fixing plate 16 T H2 DV OS T KJr2 IN OS T K4 IN OS T M50 T M32 452 EKK26 Fuse fixing plate 18 T K3 T K3 Pro T K3 SP OS T H2 DV OS T KJr2 IN OS T K4 IN OS T M50 T M32 453 EK029 Fuse fi...

Page 77: ...Jr2 IN OS T K4 IN OS 707 EK441 Switch wire T K4 IN OS 708 EKK10 Gas valve wire T K3 T K3 Pro 709 EKK11 Flame rod wire T K3 T K3 Pro 710 EKK0Z EH IG wire T K3 T K3 Pro EKK40 EH IG wire with freeze prot...

Page 78: ...T D2 IN T D2 OS Service Manual Ver 1 00 78 CONFIDENTIAL 15 Revisions Version Description of changes Date 1 00 First edition 11 01 10...

Search results

Summary of Contents for T-D2-IN

Reviews:

Related manuals for T-D2-IN

Brands by name

Popular brands

A.O. Smith T-D2-IN, Service Manual

Search results

Summary of Contents for T-D2-IN

Reviews:

Related manuals for T-D2-IN

Brands by name

Popular brands