Manual 2100-738C
Page
71 of 73
Manual
2100-532G
Page
46 of 48
Heat
Gen.
Power Failure
Blown Fuse or Tripped Breaker
Faulty Wiring
Loose Terminals
Low Voltage
Defective Contacts in Contactor
Compressor Overload
Potential Relay
Run Capacitor
Start Capacitor
Faulty Wiring
Loose Terminals
Control Transformer
Low Voltage
Thermostat
Contactor Coil
Pressure Controls (High or Low)
Indoor Blower Relay
Discharge Line Hitting Inside of Shell
Bearings Defective
Seized
Valve Defective
Motor Wingings Defective
Refrigerant Charge Low
Refrigerant Overcharge
High Head Pressure
Low Head Pressure
High Suction Pressure
Low Suction Pressure
Non-Condensables
Unequalized Pressures
Solenoid Valve Stuck Closed (Htg)
Solenoid Valve Stuck Closed (Clg)
Solenoid Valve Stuck Open (Htg or Clg)
Leaking
Defective Valve or Coil
Plugged or Restricted Metering Device (Htg)
Scaled or Plugged Coil (Htg)
Scaled or Plugged Coil (CLg)
Water Volume Low (Htg)
Water Volume Low (Clg)
Low Water Temperature (Htg)
Plugged or Restricted Metering Device (Clg)
Fins Dirty or Plugged
Motor Winding Defective
Air Volume Low
Air Filters Dirty
Undersized or Restricted Ductwork
Auxillary Heat Upstream of Coil
Compressor
W
il
l Not Run
No Pow
er at Contact
or
Compressor
W
il
l Not Run
Pow
er at Contactor
Compressor
"Hums
"
But W
ill Not
Start
Compressor
Cyc
les on Ov
erload
Thermost
at Check
Light
Lite-Lock
out
Relay
Compressor
Off on High
Pressure Control
Compressor
Off on Low
Pressure Control
Compressor
Noisy
Head Pressure T
oo High
Head Pressure T
oo Low
Suction P
ressure Too High
Suction P
ressure Too Low
I.D. Blow
er W
ill Not
Start
I.D. Coil
Frosting or Ic
ing
High Compress
or Amps
Ex
cessiv
e W
ater Us
age
Compressor
Runs Continuously
– No Cooling
Liquid Refrigerant Fl
ooding Back
To Compres
sor
Compressor
Runs Continuously
– No Heating
Rev
ersing Valv
e Does
Not Shift
Liquid Refrigerant Fl
ooding Back
To Compres
sor
Aux
. Heat on I.
D. Blow
er Off
Ex
cessiv
e Operati
on Costs
Ice in W
ater
C
oi
l
Heating Cycle
A
UX.
Cooling
Cycle
Heating or Cooling Cycles
I
n
door Blower
M
otor
and Coi
l
INDOOR SECT
ION
POW
ER SUP
PLY
W
ater
S
olenoid
R
ev
.
Valv
e
W
ater Coi
l
W
A
T
E
R COIL SE
CT
IO
N
Line V
oltage
Control Ci
rcuit
Compressor
Refri
gerant Sy
stem
QUICK
REFERENCE
TROUBLESHOOTING
CHART
FOR
WATER
TO
AIR
HEAT
PUMP
DENOTES
COMMON
CAUSE
D
E
N
O
T
E
S
O
C
C
A
S
I
O
N
A
L
C
A
U
S
E