O W N E R ’ S M A N U A L
PROBLEM
POSSIBLE CAUSE
SOLUTION
High head pressure
Low air flow.
Adjust blower speed.
Return air short cycling.
Check duct design and
readjust supply and return
air registers.
Refrigerant overcharge.
Adjust refrigerant.
(See charging procedure).
Non-condensible in system.
Evacuate and recharge
system.
Dirty coils.
Clean all coils in unit and
remote if equipped.
Dirty filters.
Replace filters.
Head pressure switch
Blower running too slow.
Adjust blower speed up.
tripping
(Same as above)
Blower turning backwards.
Change blower rotation..
(3 phase only)
Motor going off on internal
Check for rated AMP draw.
overload.
Replace motor if defective.
Dirty filters.
Replace filters.
Supply and return air registers Remove restrictions or
restricted or blocked.
blockages.
Refrigerant overcharge.
Adjust refrigerant.
(See charging procedure).
Dirty coils.
Clean all coils in unit and
remote if equipped.
Defective head pressure switch. Replace head pressure
Low head pressure
Low refrigerant charge.
Add refrigerant.
(See charging procedure).
Return air temperature too
Return air temperature
low.
must be minimum 45°F.
SERVICE DIAGNOSIS
(The following is a guide intended for use by qualified
service personnel only. CAUTION High Voltage and
refrigerant under high pressure present.)
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