Trane 4WCY4036B3 User Manual

18-BB34D1-19B-EN
23
Table 12. Demand Defrost Control Checkout Table (continued)
SYMPTOMS CHECKS
YES/NO
ACTIONS
8.
Defrost initiates on
approximately 30/45 minute
intervals.
1.
TEST_COMMON pin shorted to TST pin?
Y Remove short.
2. Do both sensors check OK?
N
Replace defective sensor (Clear coil and re
gency heat light).
Y
Complete SYMPTOM #3.
3.
Verify correct system charge. Adjust as needed.
4.
Verify a "forced defrost" terminates less
than 15 minutes.
N
Replace defrost control.
5. OD fan motor off in defrost. See SYMPTOM #9.
6.
Verify proper SOV operation. Replace if necessary.
9.
OD fan runs during defrost. Replace defrost control.
10.
No SOV delay on defrost
termination.
Has J1 been cut?
Y
The soft-switch time is defeated when J1 is
cut.
N
Replace defrost control.
11. ODS-A burned out.
B to T greater than 10 volts?
Y
Check low voltage wiring for miswire.
N
Check for short in low voltage wiring.
12.
On SCROLL bearing units,
compressor does not operate.
1. 24V R-B at board & 24V Y-B at board? N
Repair low voltage wiring.
2. Check protective devices in YO circuit.
24V YO-B present after 30 seconds.
N
Y-B signal or control may be intermittent
13. On SCROLL bearing units, no 30
second off delay at defrost
initiation.
Check voltage between control terminals 2
and 7, force a defrost cycle. Is 24V present
for 30 seconds and 0V thereafter?
N
Replace defrost control.
UUnniitt SSttaarrttuupp

Trane 4WCY4036B3 Specifications

General

Brand	Trane
Model	4WCY4036B3
Category	Heat Pump
Language	English