Carrier PG9UAA, Руководство по устранению неисправностей

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Status Code 25
MODEL SELECTION OR SETUP ERROR – If status code 25 only flashes 4 times on power--up the variable speed fur-
nace control is missing its model plug (PL4) and is defaulting to the model selection stored in memory.
If status code 25 flashes continuously it could indicate any of the following:
1. Model plug (PL4) is missing and there is no valid model stored in permanent memory. This will happen if you forget to install the
model plug (PL4) on a service replacement board.
2. Thermostat call with SW1--1 ON.
3. Thermostat call with SW1--6 ON.
4. SW1--1 and SW1--6 both ON together.
5. Two different furnace models twinned.
6. Board does not recognize model plug. Verify model plug part number to model plug table shown on furnace wiring label.
STEP ACTION YES NO GO TO
1. Turn power off, remove the blower access panel, and disconnect the R thermostat lead from
the furnace control board. 2
2. Turn power on and depress door switch. Use a piece of tape to hold switch closed. 3
3. Does status code 25 flash only 4 times on power--up? 4 6
4. The model plug is missing or invalid but the control will default to the model stored in
memory. The furnace will operate properly as if the model plug was installed. If you have
the APM program you can confirm the setting in memory.
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5. Go to page number indicated in Index for CLEANUP AND START--UP INSTRUC-
TIONS. INDEX
6. Is setup switch SW1--1 in the ON position? 7 8
7. Put setup switch SW1--1 in the OFF position. 5
8. Is setup switch SW1--6 in the ON position? 9 10
9. Put setup switch SW1--6 in the OFF position. 5
10. Is this a new service replacement control? 19 13
11. You need to remove the model plug PL4 from the old control and install it on the new re-
placement control. Once you install the model plug the power to the furnace needs to be
reset because the model plug is only read on power--up.
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12. If the model plug is not available from the old control, reference the model plug chart on
the wiring schematic for the correct part number. If absolutely necessary you can install
two resistors into the PL4 connection on the control board. R1 goes across the middle 2
pins and R2 goes across the outer 2 pins. Reference the model plug chart on the schematic
for the correct resistance values. Resistors can be purchased at a nearby Radio Shack. The
resistors need to be within 10% of the stated value. Check with an ohm meter before in-
stalling.
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13. Is this furnace twinned with another furnace? 14 17
14. Is the MAIN furnace flashing the status code? 15 17
15. Do the furnaces have the same model number on the rating plate? 18 16
16. Replace one of the furnaces because you cannot twin different size furnaces. 5
17. Replace the variable speed furnace control. 5
18. One of the model plugs is bad. Ohm out each one and replace the one that does not match
the model plug chart on the wiring schematic. 5
19. Is the model plug PL4 from the old control installed? 20 11
20. On PG9UAA furnaces make sure you have installed a furnace control date code 4106 or
later. The date code is the last 4 digits printed after the board part number in the WHITE
box near the L2 terminals on the right side of the furnace control. Reference Fig. 1 in Ap-
pendix A for the location of the board date code.
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Status Code 31
HIGH--HEAT PRESSURE SWITCH OR RELAY DID NOT CLOSE OR REOPENED -- This status code can occur under the scenarios
shown below. Keep in mind that whenever the variable speed furnace control shuts unit down, gas remains off or shuts off immediately,
inducer continues running for 15 seconds, and if the blower is running, it remains running at low heat airflow or reduces to low heat airflow
for the selected off--delay. A miswired gas valve can cause this problem so make sure the BLUE wire goes to the gas valve M terminal and
the GREEN/YELLOW wire goes to the gas valve C terminal.
-- LOW HEAT
1. PREPURGE OR STEADY--STATE -- If the high heat pressure switch input turns ON the variable speed begins flashing status code 31
and transitions to high heat. After the call for heat is satisfied and the blower off--delay is completed the control will stop displaying status
code 31.