Operating instructions

15
PROBLEM POSSIBLE CAUSE CHECKS AND CORRECTIONS
Rattles and Vibrations Check for loose screws, panels, or internal components. Tighten
and secure. Copper piping could be hitting the metal surfaces.
Noisy Carefully readjust by bending slightly.
Operation Water and Airborne Undersized ductwork will cause high airflow velocities and noisy
(Continued) Noises operation. Excessive water through the water-cooled heat
exchanger will cause a squealing sound. Check the water flow to
ensure adequate flow for good operation, while eliminating the
noise.
Dirty Air Filter Check filter. Clean or replace if found dirty.
Airflow Lack of adequate airflow or improper distribution of air. Check the
motor speed and duct sizing. Check the filter, it should be inspected
Evaporator every month and changed if dirty. Check for closed registers.
(air coil) Remove or add resistance accordingly.
ices over Evaporator Blower Motor Check for overheated evaporator blower motor and tripped
Tripping Off on Overload overload. Replace motor if necessary.
Unit Operating at Too Low If room temperature drops below 65 degrees, the evaporator may
a Room Temperature ice over.
Unit Not Level or Pitched Level vertical units, and horizontal units which use bottom condensate
Water drips Correctly drain. Pitch horizontal units that use side condensate drain.
from unit Condensate Drain Line Clean condensate drain.
Kinked or Plugged
XIII. TROUBLESHOOTING GUIDE FOR LOCKOUT CONDITIONS
If the heat pump goes into lockout on a high or low pressure switch, the cause of the lockout can be narrowed down by
knowing the operating mode and which pressure switch the unit locked out on. The following table will help track down the
problem once this information is known. NOTE: A lockout condition is a result of the heat pump shutting itself off to
protect itself. Never bypass the lockout circuit. Serious damage can be caused by the system operating without lockout
protection.
MODE LOCKOUT CONDITION POSSIBLE CAUSE
High Pressure (Head) -Loss/lack of airflow through air coil (dirty air filter, closed vents,
(Condenser/Air Side) blower, restricted ductwork, etc.)
Heating -High air temperature entering heat pump
-Dirty (fouled) air coil
-Extremely high water temperature to the evaporator, raising
compressor capacity and overloading condenser
-Overcharged refrigerant circuit
Low Pressure (Suction) -Loss/lack of flow through earth coupled coil
(Evaporator/Earth -Low fluid temperature operation in the earth loop
Coupled Side) -Freezing fluid in heat exchanger (lack of antifreeze)
-Undercharged/overcharged refrigerant circuit
-Expansion valve/sensing bulb malfunction
High Pressure (Head) -Loss/lack of water flow
(Condenser/Earth -High fluid temperature operation in the earth loop
Coupled Side) -Dirty (fouled) condenser coil
Cooling -Overcharged refrigerant circuit
Low Pressure (Suction) -Loss/lack of airflow through air coil (dirty filter, closed vents,
(Evaporator/Air Side) blower, restricted ductwork, etc.)
-Low air temperature entering the heat pump (thermostat setpoint
too low, etc.)
-Air coil freezing up (low airflow, lack of charge, etc.)
-Undercharged/overcharged refrigerant circuit
-Expansion valve/sensing bulb malfunction