Trane A4AC3029A Installer's Guide

88-A4AC3001-1H-EN 25
Is contactor
energized?
(contacts closed)
Is voltage
present at
contactor coil?
Replace contactor
YES
NO
NO
Check for 24 volts AC
across contactor coil
Check control
transformer and
control fuse
Is the control
transformer
and fuse good?
NO
YES
Repair or replace
transformer or fuse.
Investigate cause for
failure (possible short in
field wiring)
Jumper R to Y low
voltage terminals
at thermostat sub
base.
Does the
contactor
energize?
NO
Repair or replace
connecting wiring
YES
Go To: Compressor won’t run
Replace the room
thermostat
YES
Compressor fails to start
Contactor check
L2 L1
T2 T1
IN
OUT
L2 L1
T2 T1
Single Pole Contactor (MS)* Double Pole Contactor (MS)*
Contactor Coil
24 VAC
HIGH
VOLTAGE
IN
OUT
HIGH
VOLTAGE
*Refer to Wiring Diagram to determine if a single pole or double pole contactor is used.
TROUBLESHOOTING
15.2 Troubleshooting

Trane A4AC3029A Specifications

General

Brand	Trane
Model	A4AC3029A
Category	Heat Pump
Language	English