Carrier R-22 Application Manual And Service Manual page 20

OF1 OF2
G
E
W2
14
L
G
W3
R
R
Y
R
O
Y
C
O
50 90
W1
HK32FA003/HK32FA006
G
E
W2
L
W3
R
Y
O
C
W1
across defrost thermostat leads using ohmmeter. Resistance of
zero indicates defrost thermostat is closed and operating
properly.
9. Short between the speed-up terminals using a thermostat
screwdriver. This reduces the timing sequence to 1/256 of
original time. (See Fig. 20 and Table 11.)
NOTE: Since Fig. 20 shows timing cycle set at 90 minutes, unit
initiates defrost within approximately 21 sec. When you hear the
reversing valve change position, remove screwdriver immediately.
Otherwise, control will terminate normal 10-minute defrost cycle
in approximately 2 sec.
C
C
C
C
DFT
Fig. 20—Inserting Jumper Wire
OF2 OF1
14
G C
C
R
R C
C
Y
O DFT
30 50
HK32FA003/HK32FA006
Fig. 21—Checking Between C and W2
A88404
A88403
Exercise extreme caution when shorting speed-up pins. If pins
are accidentally shorted to other terminals, damage to the
control board will occur.
10. Unit is now operating in defrost mode. Check between C and
W2 using voltmeter as shown in Fig. 21. Reading on voltmeter
should indicate 24v. This step ensures defrost-relay contacts
have closed, energizing supplemental heat (W2) and
reversing-valve solenoid (O).
11. Unit should remain in defrost no longer than 10 minutes.
Actual time in defrost depends on how quickly speed-up
jumper is removed. If it takes 2 sec. to remove speed-up
jumper after unit has switched to defrost, the unit will switch
back to heat mode.
20
OF2
OF1
TEST 30 50 90
O R T2 Y TI DFT C
W1
O
R
W2
Y
C
CES0110063,
CES0130024
A91444
OF2
OF1
O R T2 Y TI DFT C TEST 30 50 90
W1
O
R
W2
Y
C
CES0110063,
CES0130024
A91443