- 32 -
Status Code 4 + 1
BLOWER MOTOR FAULT - This status code indicates the blower failed to reach 250 RPM or the blower failed to
communicate to the modulating furnace control within 30 seconds after being turned ON or within 10 seconds during
steady-state operation.
STEP
ACTION
YES
NO
GO TO
1.
Shut the power off, remove the blower door and disconnect communication connector PL7
(if used) or the R thermostat lead (if used) from the furnace control board.
2
2.
Turn the power on and depress the door switch. Use a piece of tape to hold it closed.
3
3.
Jumper the R and W/W1 thermostat terminals.
4
4.
Observe the operation of the furnace for the next 5 minutes or until fault occurs.
5
5.
Does status code 4 + 1 flash?
9
6
6.
Does a different status code flash?
7
8
7.
Go to page number indicated in the Index for the section covering the status code.
INDEX
8.
Go to page number Indicated in Index for CLEANUP AND START-UP INSTRUCTIONS.
INDEX
9.
Did the blower motor turn ON and come up to speed before status code flashes?
35
10
10.
Remove tape from door switch and turn power off at main disconnect.
11
11.
Does the blower wheel rub against blower housing?
12
13
12.
Fix the problem.
8
13.
Does the blower wheel turn freely?
14
15
14.
Is blower wheel firmly mounted on motor shaft?
16
12
15.
Replace the entire blower motor or blower control module attached to the blower motor. If
you replace the blower control module go to step 41. Always inspect failed motor for water
damage. If present, find source of water and fix it. Check A-coil and/or humidifier.
12
16.
Disconnect jumper wire across R and W/W1 thermostat terminals.
17
17.
Are all pins and wire leads intact on connectors between the modulating furnace control and
the blower motor.
18
12
18.
Turn the power on and depress the door switch. Use a piece of tape to hold it closed.
19
19.
Do you have 115-vac across the BLACK blower motor wire connected to L1 and the WHITE
blower motor wire connected to L2?
21
20
20.
Replace the modulating furnace control.
8
21.
Do you have 115-vac across the BLACK and WHITE power leads at the blower motor?
23
22
22.
You have an open wire or bad terminal on either the BLACK or WHITE wire between the
modulating furnace control and the blower motor. If you have a power choke disconnect it
and check for continuity.
12
23.
Check the blower 12-vdc supply. To do this connect a DC voltmeter across terminals PL3-1
RED (+) and PL3-2 GREEN (-). Is there 12-vdc across the RED and GREEN blower wires?
24
20
24.
Connect a DC voltmeter across the RED (+) and GREEN (-) wires at connector PL13. Is
there 12-vdc across the RED and GREEN blower wires?
26
25
25.
You have an open wire or bad terminal on either the RED or GREEN wire between
connectors PL3 and PL13. Repair it or replace harness.
8
26.
Check the blower motor serial input signal. To do this disconnect PL3 from the furnace
control and connect a DC voltmeter across terminals PL3-3 (+) and PL3-2 (-) on the
modulating furnace control. Is there 5-vdc across PL3-3 and PL3-2?
Note:
The voltage should be very stable and should not fluctuate more than .02-vdc. If the
voltage fluctuates get a different volt meter before going on to the following steps.
Note:
Since the modulating furnace control and the blower motor are continuously
communicating you do not actually need to run the blower motor to troubleshoot the PL3
connection.
27
20
27.
Reconnect PL3 to the modulating furnace control and connect a DC voltmeter across
terminals PL3-3 YELLOW (+) and PL3-2 GREEN (-). Does the voltage appear to fluctuate
more than it did in step 26?
Note:
Typical voltmeters will show a fluctuation of .2-vdc to 1-vdc. The amount of
fluctuation is not important and you could see even more fluctuation depending on the
voltmeter you use.
28
20
440 08 4001 00
Содержание 9MAC/E series
Страница 39: ...39 Fig 2 Wiring Schematic 440 08 4001 00...
Страница 41: ...41 Figure 3 ECM Blower Motor 440 08 4001 00...
Страница 48: ...48 Replaces New Form ICP Eng 3 12 440 08 4001 00...
