Bryant 333B-AV-036060-AA-JA Troubleshooting Manual page 15

STEP
18. Does status code 21 ever flash?
Go to page number indicated in Index for CLEANUP AND START-UP IN-
STRUCTIONS. If problem persists on an intermittent basis, replace 2-stage fur-
19.
nace control. If problem still persists on an intermittent basis after replacing
2-stage furnace control, contact your distributor.
Status Code 22
ABNORMAL FLAME-PROVING SIGNAL—THIS STATUS CODE INDICATES FLAME SIGNAL WAS SENSED WHILE GAS VALVE
GV WAS DE-ENERGIZED. THE INDUCER WILL RUN UNTIL FAULT IS CLEARED.
STEP
1. Turn off gas to furnace by shutting off external manual shutoff valve.
2. Does status code 22 stop flashing?
3. Replace gas valve.
4. Replace 2-stage furnace control.
Go to page number indicated in Index for CLEANUP AND START-UP IN-
5.
STRUCTIONS.
Status Code 23
LOW-HEAT PRESSURE SWITCH DID NOT OPEN—THIS STATUS CODE INDICATES LOW-HEAT PRESSURE SWITCH LPS IS
MADE WHEN A CALL FOR HEAT IS INITIATED. THE 2-STAGE FURNACE CONTROL WILL FLASH STATUS CODE 23 UNTIL
SWITCH OPENS, THEN CYCLE BEGINS.
STEP
1. Turn power off, remove blower door, and disconnect R thermostat lead.
Turn power on and depress door switch. Use a piece of tape to hold switch
2.
closed.
3. Jumper R and W/W1 thermostat terminals.
4. Does status code 23 flash?
5. Does a different status code flash?
6. Go to page number indicated in Index for section covering the status code.
Go to page number indicated in Index for CLEANUP AND START-UP IN-
7.
STRUCTIONS.
Do you have 24 vac across YELLOW wire on low-heat pressure switch LPS
8.
and C -24V on 2-stage furnace control?
OM
Do you have 24 vac across connector terminal PL1-5 and C
9.
furnace control?
10. The main harness is miswired.
11. Rewire low-heat pressure switch LPS per wiring diagram.
12. Replace 2-stage furnace control.
13. Is low-heat pressure switch LPS wired correctly?
14. Replace pressure switch assembly.
ACTION
ACTION
ACTION
-24V on 2-stage
OM
—15—
YES NO GO TO
11 19 —
— — INDEX
YES NO GO TO
— — 2
3 4 —
— — 5
— — 5
— — INDEX
YES NO GO TO
— — 2
— — 3
— — 4
8 5 —
6 7 —
— — INDEX
— — INDEX
13 9 —
10 12 —
— — 11
— — 7
— — 7
14 11 —
— — 7