About Trane and American Standard Heating and Air Conditioning
Trane and American Standard create comfortable, energy efficient indoor environments for residential applications.
For more information, please visit www.trane.com or www.americanstandardair.com
The AHRI Certified mark indicates company participation in the AHRI Certification program. For verification of individual certified products, go to
ahridirectory.org.
The manufacturer has a policy of continuous data improvement and it reserves the right to change design and specifications without notice. We are
committed to using environmentally conscious print practices.
© 2020
88-M4PW004-1B-EN 24 Apr 2020
Supersedes 88-M4PW004-1A-EN (March 2018)
SYSTEM FAULTS
REFRIGERANT CIRCUIT
Head Pressure Too High
Head Pressure Too Low
Suction Pressure Too High
Suction Pressure Too Low
Liquid Refrig. Floodback (TXV/EEV)
Liquid Refrig. Floodback
(Cap. Tube)
I.D. Coil Frosting
Compressor Runs
Inadequate or No Cooling/Htg
ELECTRICAL
Compressor & O.D. Fan
Won’t Start
Compressor Will Not Start
But O.D. Fan Runs
O.D. Fan Won’t Start
Compressor Hums But Won’t Start
Compressor Cycles on IOL
I.D. Blower Won’t Start
DEFROST
Unit Won’t Initiate Defrost
Defrost Terminates on Time
Unit Icing Up
WH
AT
TO
C
HE
CK
M
OD
E
PO
WE
R S
UP
PLY
HIG
H V
OLT
AG
E W
IRIN
G
CO
MP
RE
SS
OR
IO
L
RU
N C
APA
CIT
OR
STA
RT
CA
PAC
ITO
R
STA
RT
RE
LAY
CO
NTA
CTO
R C
ON
TAC
TS
LO
W V
OLT
AG
E W
IRIN
G
CO
NT
RO
L T
RA
NS
FO
RM
ER
TH
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MO
STA
T
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OIL
LO
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OM
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ND
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DE
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.D.
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EV
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RE
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FLO
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RE
STR
ICT
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SO
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D
EFE
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*
DE
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DE
FR
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TR
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DE
F.
C
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C
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C
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C
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C
H
C
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C
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C
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P
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P
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S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
P
P
P
P
S
S
S
S
P
P
P
P
S
S
P
P
P
P
P
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P
P
P
P
P
P
P
P
S
S
S
S
S
S
S
S
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
P
S
S
S
S
S
S
S
P
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
S
P
P
S
S
S
S
S
S
S
S
S
S
S
S
P
P
P
P
P
P
S
S
S
S
S
S
S
S
S
S
S
P
P
S
S
S
S
S
S
S
S
P
P
P
P
P
P
P
S
S
P P
P
P
C - Cooling H - Heating P - Primary Causes S - Secondary Causes
*
- 3 Phase Only
15.2 Troubleshooting