Service Manual

SERVICE MANUAL (C,H,T)VA9 & (C,H,T)VH8
421 08 5600 02 19
Specifications subject to change wi thout notice.
Heat Outdoor Airflow too
low or off
Check O utdoor for clogging (ice or debris) and
clean or de- ice if necessary; Troubleshoot
Outdoor fan motor and make sure it is working;
follow Outdoor Airflow troubleshooting
instruction
Heat Undercharged
System
Check charge in heating mode per heating
check charge chart. If pressures do not match
then pull out charge, weigh in using heating
charge method
Both RestrictioninFilter
Drier
Check for temperature drop across filter drier
and replace if necessary
Both Expansion Device
Restriction
If short lineset (less than 15 ft.) Troubleshoot
TXV (see guide below); replace if necessary
84 System
Malfunction
HIGH PRESSURE
LOCKOUT FOR 4
HOURS
(Elevated from fault
code 31 when the
4Hours Cool Outdoor Airflow too
low or off
Check Outdoor Coil for clogging (ice or debris)
and clean or de- ice if necessary; Troubleshoot
Outdoor fan motor and make sure it is working;
follow Outdoor Airflow troubleshooting
instruction
stage (speed) can no
longer be lowered)
Cool Overcharged System Check system charge using Cooling Charging
Mode (follow proper charging procedures)
Cool TXV malfunction (Indoor) causing an overcharged condition
Cool RestrictioninEXV
assembly plus Long
Line Application
leading to
Overcharge when
charging in Cooling
mode
Troubleshoot EXV
Cool Restriction in Circuits
or Tubing
Repair restriction
Heat Indoor Airflow too
low or off
Troubleshoot indoor fan motor and make sure
it is operating; follow indoor airflow
troubleshooting instruction. Check Indoor coil
or filter for restriction (debris) and clean if
necessary;
Heat Furnace plus Heat
pump application:
Furnace stuck on
If not in Defrost and Furnace is running same
time as heat pump, troublesh oot Furnace
Heat Overcharged System Remove refrigerant, evacuate and recharge
system using weigh in method. Return to check
charge to sub- cooling when conditions are
favorable in cooling mode
Heat Reversing Valve
Stuck in Cooling
troubleshoot reversing valve
Both Service Valve left
closed (Liquid or
Vapor)
Ensure Service Valves are open
Both Loose High Pressure
Switch harness leads
Check HPS harness, pins and connectors
Both Pressure Switch
disconnected from
the inverter
Check HPS connection to the inverter
Both Restriction of filter
drier
Check for temperature drop across filter drier
and replace if necessary
Both Non- condensable
leading to high
pressure situation
Remove refrigerant, replace filter drier,
evacuate and recharge system
Both Faulty Pressure
Switch
Check Discharge pressure with gauge, if less
than 600 +/- 20 psig and switch is open
(measure resistance) then replace pressure
switch
Both Expansion Device
Restriction
Troubleshoot TXV
Troubleshoot EXV