30. | Does blower wheel rub against blower housing? | 16 | 31 | Ð | ||
31. | Does blower wheel turn freely? | 32 | 33 | Ð | ||
32. | Is blower wheel firmly mounted on motor shaft? | 34 | 16 | Ð | ||
→33. | Replace blower motor or blower control module attached to the blower motor. If you replace the |
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blower control module go to step 51. Always inspect failed motor for water damage. If present, find | Ð | Ð | 16 | |||
| source of water and fix. Check |
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34. | Put setup switch | Ð | Ð | 35 | ||
35. | Turn power on and depress door switch. Use a piece of tape to hold switch closed. Wait a few sec | Ð | Ð | 36 | ||
for self test before proceeding to next step. | ||||||
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36. | Do you have 120v between B1 and B2 on furnace control board? | 37 | 16 | Ð | ||
37. | Do you have 120v between BLACK and WHITE power leads at blower motor MTR2? | 39 | 38 | Ð | ||
38. | You have an open wire or bad terminal on either the BLACK or WHITE wire between furnace con- | Ð | Ð | 17 | ||
trol board and blower motor MTR2. Repair it or replace blower harness(es). | ||||||
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| Check Blower ON/OFF line. To do this, connect a DC voltmeter across terminals |
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39. | and |
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voltage across RED and BLUE wires change between states as shown below? | 42 | 40 | Ð | |||
| · | State 1ÐOFF |
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| · | State 2ÐON (9.0 Ð 10.0 vdc) |
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| Disconnect PL3 from furnace control board and connect a DC voltmeter across terminals |
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| and |
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40. | OFF and then back ON. Does voltage across | 33 | 22 | Ð | ||
below? | ||||||
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| · | State 1ÐOFF |
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| · | State 2ÐON (11.0 Ð 12.0 vdc) |
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41. | You have an open wire or bad terminal on either the RED or BLUE wire between connectors PL13 | Ð | Ð | 17 | ||
and PL3. Repair it or replace blower harness(es). | ||||||
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| Connect a DC voltmeter across RED (+) and BLUE |
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42. | NENT TEST by turning setup switch |
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BLUE wires change between states as shown below? | 43 | 41 | Ð | |||
| · | State 1ÐOFF |
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| · | State 2ÐON (9.0 Ð 10.0 vdc) |
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43. | Put setup switch | Ð | Ð | 44 | ||
| Check Blower PW line. To do this, connect a DC voltmeter across terminals |
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44. | in ON position. Does voltage across RED and YELLOW wires change between states as shown |
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below? | 46 | 45 | Ð | |||
| · | State 1ÐOFF |
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| · | State 2ÐLOW (2.5 Ð 3.0 vdc) |
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| · | State 3ÐHIGH (7.0 Ð 7.5 vdc) |
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| Disconnect PL3 from furnace control board and connect a DC voltmeter across terminals |
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| and |
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45. | OFF and then back ON. Does voltage across |
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below? | 33 | 22 | Ð | |||
| · | State 1ÐOFF |
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| · | State 2ÐLOW (3.0 Ð 4.0 vdc) |
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| · | State 3ÐHIGH (9.0 Ð 10.0 vdc) |
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| Connect a DC voltmeter across RED (+) and YELLOW |
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| PONENT TEST by turning setup switch |
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46. | and YELLOW wires change between states as shown below? | 33 | 47 | Ð | ||
· | State 1ÐOFF | |||||
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| · | State 2ÐLOW (2.5 Ð 3.0 vdc) |
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| · | State 3ÐHIGH (7.0 Ð 7.5 vdc) |
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47. | You have an open wire or bad terminal on either the RED or YELLOW wire between connectors | Ð | Ð | 17 | ||
PL13 and PL3. Repair it or replace blower harness(es). | ||||||
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| Check RPM feedback line. To do this, connect a DC voltmeter across terminals |
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| and |
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48. | back ON. Does voltage across ORANGE and VIOLET wires change between states as shown be- |
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low? |
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| · | State 1ÐOFF (12.0 Ð 12.5 vdc) |
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| · State 2ÐLOW (10.7 Ð 11.7 vdc) |
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| · | State 3ÐHIGH (9.7 Ð 10.7 vdc) |
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| Connect a DC voltmeter across ORANGE (+) and VIOLET |
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| COMPONENT TEST by turning setup switch |
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49. | ORANGE and VIOLET wires change between states as shown below? | 50 | 33 | Ð | ||
· | State 1ÐOFF (12.0 Ð 12.5 vdc) | |||||
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| · State 2ÐLOW (10.7 Ð 11.7 vdc) |
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| · | State 3ÐHIGH (9.7 Ð 10.7 vdc) |
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50. | You have an open wire or bad terminal on either the ORANGE or VIOLET wire between connectors | Ð | Ð | 17 | ||
PL13 and PL3. Repair it or replace blower harness(es). | ||||||
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