Amana
Furnace

Model # SU-125B3 Official Amana gas-fired upflow furnace

Here are the diagrams and repair parts for Official Amana SU-125B3 gas-fired upflow furnace, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 197 parts  |

Plastic Washers (2 Req.) 20-5057
#10

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Plastic washers (2 req.)

Part #20-5057

The manufacturer no longer makes this part, and there's no substitute part

Furnace Blower Wheel 20-5047
#5B

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Furnace blower wheel

Part #20-5047

The manufacturer no longer makes this part, and there's no substitute part

Blower Access Door Assembly 251-2450
#36B

(su-75) (su-100) (su-125) (su-150) (su-175) (su-200) diagram

Blower access door assembly

Part #251-2450

The manufacturer no longer makes this part, and there's no substitute part

Pressure Regulator (v5107) 75,000-125,000 Input - Nat. G 21-0595
Pressure regulator (v5107) 75,000-125,000 input - nat. g

Part #21-0595

The manufacturer no longer makes this part, and there's no substitute part

Blower Assembly (w/motot) 980-0779
#1E

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Blower assembly (w/motot)

Part #980-0779

The manufacturer no longer makes this part, and there's no substitute part

Furnace Blower Housing 980-1257
#3

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Furnace blower housing

Part #980-1257

The manufacturer no longer makes this part, and there's no substitute part

Blower Assembly (w/motor) 980-0272
#1C

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Blower assembly (w/motor)

Part #980-0272

The manufacturer no longer makes this part, and there's no substitute part

Burner Tube Spacer 975-1046
#40C

(su-75) (su-100) (su-125) (su-150) (su-175) (su-200) diagram

Burner tube spacer

Part #975-1046

The manufacturer no longer makes this part, and there's no substitute part

Motor Direct Drive 20-9137
#13B

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Motor direct drive

Part #20-9137

The manufacturer no longer makes this part, and there's no substitute part

Air Filter - 20 X 25 X 1 - Hi-velocity (1 Per) 22-1144
#26

(su-125ah) (su-125a3) (su-125a4) (su-125bh) (su-125b3) (su-125b4) (su-150ah) (su-150a3) (su-150a4) (su-150bh) (su-150b4) (su-150b5) (su-175bh) (su-175b4) (su-175b5) (su-200bh) (su-200b5) (su-200b6) diagram

Air filter - 20 x 25 x 1 - hi-velocity (1 per)

Part #22-1144

The manufacturer no longer makes this part, and there's no substitute part

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Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

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