A O Smith 974 Series Parts List BTH 300A 400A 975 Com Gas 197177 001 0206.p65
975 Series 197177-001
975 Series to the manual ebfd65d9-82d6-4504-966e-2d29962631f2
2015-01-05
: A-O-Smith A-O-Smith-974-Series-Parts-List-162804 a-o-smith-974-series-parts-list-162804 a-o-smith pdf
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1
PRINTED IN THE U.S.A. 0206 PART NO. 197177-001
BLOWER/BURNER ASSEMBLY
See Page 7
GAS VALVE
See Page 5
RECIRCULATING SYSTEM
See Page 5
OPERATING CONTROL WIRING
See Page 4
CONTROL PANEL
See Page 3
POWERED ANODE ASSEMBLY
See Page 8
CYCLONE XHE - MODEL BTH-300A/400A
See Page 2
EXHAUST ELBOW, VENT KIT & BLOWER
INTAKE PARTS
See Page 6
COMMERCIAL WATER HEATER PARTS LIST
Model BTH-300A
Model BTH-400A
Series 974/975
2
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Cleanout Gasket ............. 99038 ...........99038
2 Cover, Cleanout .............. 99037 ...........99037
3 Cover, Left ..................... 194748 .........194748
4 Cover, Right ................... 194749 .........194749
5 Drain Valve ................... 26273-4 ........ 26273-4
7 Labels:
800 Help Line ................. 190600 .........190600
C.E.C. ............................. 42985 ...........42985
Cleanout.......................... 78754 ...........78754
ECO ............................. 192282-1...... 192282-1
Electronic Ignition............ 77860 ...........77860
Flammable Vapors ..... 184872-000 .. 184872-000
Lighting & Operating ...... 194548 .........194548
Relief Valve .................... 191068 .........191068
UL .................................. 192870 .........192870
Ultra Coat ....................... 193860 .........193860
Warning ......................... 193912 .........193912
Water Inlet ...................... 94519 ...........94519
Water Outlet.................... 94518 ...........94518
Wiring Diagram .............. 194772 .........194772
8 Panel, Back .................... 194750 .........194750
9 Temperature and
Pressure Relief Valve ... 99383-3 ........ 99383-3
CYCLONE XHE BTH 300A/400A - PARTS LIST
NOTE: Underlined parts are recommended
stock items for emergency replacement.
Consider gas used in your area only.
*Not illustrated.
Standard hardware items may be
purchased locally.
3
CYCLONE XHE BTH 300A/400A - CONTROL PANEL
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Cable Assembly, Power Switch ................................................................. 194785 ........... 194785
2 Blower Prover Air Switch ........................................................................... 194706 ........... 195013
3 Box, Anode ................................................................................................ 194857 ........... 194857
4 Box, Junction ............................................................................................. 194126 ........... 194126
5 Cable Assembly, Low Voltage ................................................................... 194918 ........... 194918
7 Wire Harness ............................................................................................ 194783 ........... 194783
8 Cable, Assembly - Controls ....................................................................... 194784 ........... 194784
9 Wire Assembly - Air Flow Switch..............................................................192802-2.........192802-2
10 Wire Assembly - Air Flow Switch.............................................................192802-1.........192802-1
Control Board, Cable Assembly (Includes Item 11 & 11A) ........................ 194811 ........... 195018
11 Control Board ......................................................................................... 194812 ........... 195010
11A Cable Assembly ..................................................................................... 194809 ........... 194809
12 Display Board ............................................................................................ 194808 ........... 194808
13 Electronic Control ...................................................................................... 194747 ........... 194747
14 Probe, Upper ............................................................................................. 192606 ........... 192606
15 Probe, Lower ............................................................................................. 192609 ........... 192609
16 Switch, Blocked Inlet ................................................................................. 194911 ........... 195012
17 Switch, Blocked Outlet - NAT .................................................................... 194910 ........... 194910
Switch, Blocked Outlet - LP ....................................................................... 195017 ........... 195017
18 Pump, Recirculation .................................................................................. 196915 ........... 196915
19 Switch, On/Off ........................................................................................... 193243 ........... 193243
20 Switch, NAT, Low Gas Pressure ............................................................191149-6.........191149-6
Switch, LP ,Low Gas Pressure .................................................................191149-4.........191149-4
21 Transformer............................................................................................... 192608 ........... 192608
22 Valve, Natural Gas ...................................................................................194536-5.........194536-5
22 Valve, LP Gas ..........................................................................................194536-6.........194536-6
23 Tubing, 1/4" ID, PVC ................................................................................. 193738 ........... 193738
24 Cable Assembly, Igniter............................................................................. 194937 ........... 194937
CYCLONE XHE BTH 300A/400A - OPERATING CONTROLS & WIRING (See Next Page)
BTH300A BTH400A
Item Description 974/975 974/975
1 Board, Display Panel ............................ 194808 ........... 194808
2 Bracket, Mounting Left ........................194123-1........ 194123-1
3 Bracket, Mounting Right ....................... 194123 ........... 194123
Control Board, Cable Assembly
(includes 4 & 4A) .................................. 194811 ........... 195018
4 Control Board .................................... 194812 ........... 195010
4A Cable Assembly ................................ 194809 ........... 194809
5 Junction Box Assembly ........................ 194126 ........... 194126
6 Junction Box Cover ................................ 2233 ............... 2233
7 Label, Display Panel ............................. 194203 ........... 194203
8 Label, Led............................................. 194915 ........... 194915
9 Panel Front ........................................... 193884 ........... 193884
10 Screw, Plastic ....................................... 194202 ........... 194202
11 Switch,Off/On ....................................... 193243 ........... 193243
12 Splatter Shield .................................... 197117-000
4
DETAIL 2 - CYCLONE XHE BTH 300A/400A - CONNECTIONS (Continued)
5
DETAIL 4 - GAS VALVE
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Pump, Recirculation ............................................................................... 196915 ................196915
2 Elbow, 3/4" Male - 1" Female ................................................................. 194872 ................194872
3 Di-Electric Union..................................................................................... 196941 ................196941
4 Vent, Automatic Air................................................................................. 194830 ................194830
5 Tube, Inlet .............................................................................................. 194820 ................ 194820
6 Tube, Closed End Dip ............................................................................ 194924 ................194924
RECIRCULATING SYSTEM
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Nipple, 3/4" - Pipe...................................... 85040-18 ...... 85040-18
2 Nipple, 1/8" - Pipe...................................... 192948-2 ...... 192948-2
3 Pipe, Union ...................................................95515 ............ 95515
4 Switch, Low Gas Pressure ........................ 191149-6 ...... 191149-6
LP Gas .................................................... 191149-4 ...... 191149-4
5 Tee, Non-Reducing ......................................40119 ............ 40119
6 Valve, NAT Gas......................................... 194536-5 ...... 194536-5
Valve, LP Gas ........................................... 194536-6 ...... 194536-6
7 Orifice, NAT............................................. 192477-268 .. 192477-304
Orifice, LP ............................................... 192477-185 .. 192477-221
8 Orifice holder ...............................................192447 .......... 192447
Standard hardware items may be purchased locally.
6
BTH 300A BTH 400A
Item Description 974/975 974/975
EXHAUST ELBOW AND FITTINGS
1 Adapter, Hose Fitting....................................................................................................... 192472............. 192472
2 Elbow, 90° ....................................................................................................................... 195294............. 195294
3 Nipple, Pipe, Closed ........................................................................................................ 194558............. 194588
4 Plug, Hex ......................................................................................................................... 194560............. 194560
5 Tee .................................................................................................................................. 194559............. 194559
6 Tubing .......................................................................................................................... 191746-72 ........ 191746-72
7 Connector, Exhaust ......................................................................................................... 192636............. 192636
8 Hose Clamp, 3" ............................................................................................................... 192696............. 192696
9 Hose Clamp, 4.5" ............................................................................................................ 192697............. 192697
VENT KIT PARTS
10 Elbow w/Screen ............................................................................................................... 192815............. 192815
11 Intake Terminal ............................................................................................................... 182167............. 182167
12 Wall Plates (2 Req'd)....................................................................................................... 181557............. 181557
13 Silicone Sealer, 2 oz. tube ............................................................................................... 181564............. 181564
BLOWER INTAKE PARTS
14 Coupling .......................................................................................................................... 182094............. 182094
15 Hose Clamp..................................................................................................................... 194838............. 194838
16 Tube, Intake .................................................................................................................... 194923............. 194923
17 Vent Terminal, Intake ...................................................................................................... 196745............. 195736
# Dash number indicates inches.
* Not Illustrated.
EXHAUST ELBOW, VENT KIT & BLOWER INTAKE PARTS
11
12
13
14
15
15
16
17
7
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Burner.................................................................................................. 194779 ................194998
2 Blower/Motor Assembly ....................................................................... 194746................ 194746
3 Flange-Burner ..................................................................................... 194960 ................194960
4 Gasket ................................................................................................. 194817................194817
5 Gasket, Burner .................................................................................... 194777................ 195016
6 Gasket-Viewport .................................................................................. 194827................ 194827
7 Ignitor .................................................................................................. 192334 ................192334
8 Screw, #8-18 x 1/2 .............................................................................. 192698................192698
9 Screw, Socket Head Cap .................................................................... 192515 ................ 192515
10 Screw, Truss Hd. Mach 1/4-20 x 2.00 . ............................................... 194816 ................194816
11 Sensor, Flame ................................................................................... 194776-1 ............ 194776-1
12 Window, Observation ......................................................................... 98758-3 .............. 98758-3
13 Hex Nut ............................................................................................... 196882 ................ 196882
Standard hardware items may be purchased locally.
BLOWER/BURNER - ASSEMBLY
8
A.O. Smith Water Heater Parts Fulfillment
125 Southeast Parkway
Franklin, TN 37068
1-800-433-2545
www.hotwater.com
BTH 300A BTH 400A
Item Description 974/975 974/975
1 Anode ........................................................................................................ 194787 .......... 194787
2 Anode Wire, 28" ........................................................................................ 194925 .......... 194925
3 Control Box................................................................................................ 194857 .......... 194857
4 LED w. Lead Wire ..................................................................................... 194959 .......... 194959
POWERED ANODE ASSEMBLY
