Carrier 38GP - Manual (Page 6)

2.
3.
Check fan motor and blade for cleanliness and lubrica­
tion each cooling season. Clean and lubricate as
necessary.
Check electrical connections for tightness and controls
for proper operation each cooling season. Service as
necessary.
A. Condenser Coil
Remember to disconnect electrical power before removing
any panels.
Since the air is drawn into the sides of the unit and dis­
charged out the top, most of the dirt will collect on the out­
side surface of the coil. However, some dirt will penetrate
the coil. This condition is very difficult to see without
removing the top cover.
To properly check the condenser coil for cleanliness, or to
clean the coil; proceed as follows:
1. Remove top cover. Enough motor wire is provided so
that the top cover can be lend on edge without discon­
necting the motor leads. (CHp wire tie to release wire.)
2. Clean coil by spraying from inside outward with high-
velocity stream of water. (Garden hose is sufficient.)
Be careful not to damage the coil fins. Be sure to wash the
dirt from the coil. Space has been provided under the coil to
flush away the dirt. Drain holes are also provided in the
base pan. Be sure they are open. If the coil is coated with oil
or grease, it can be cleaned with a mUd detergent or an ap­
proved coil cleaning agent, then rinsed with clear water. Be
careful not to get water in the compressor and unit control
boxes.
B. Condenser Fan Motor and Blade
Remember to disconnect electrical power before removing
any panels.
1. Remove screws holding top cover.
2. Lift top with motor and fan blade out of hole. Do not
cut or stretch motor electrical leads. Be careful not to
bend fan blade.
3. Clean motor and blade with soft brush or rag. Be care­
ful not to disturb balance weights on fan blade.
4. Check fan blade setscrew for tightness.
5. Lubricate fan motor.
a. Remove dust caps or plugs from oil holes located at
each end of motor.
b. Use teaspoon, 5cc, 3/16 oz, or 16 to 25 drops of good
grade SAE 20 nondetergent motor oil in each hole.
AUow time for total quantity to be absorbed by each
bearing.
c. Wipe excess oil from motor housing.
d. Replace dust caps or plugs in oil holes.
TABLE X—TROUBLE ANALYSIS CHART
SYMPTOM CAUSE REMEDY
Compressor and condenser
fan will not start
Power failure Call power company.
Fuse blown or circuit breaker tripped Replace fuse or reset circuit breaker.
Defective thermostat, contactor,
or control relay
Replace component.
Low line voltage Determine cause and correct.
Incorrect or faulty wiring Check wiring diagram and rewire correctly.
Thermostat setting too high ♦Lower thermostat setting below room temperature.
Compressor will not start,
but condenser fan runs.
Faulty wiring or loose connections in
compressor circuit
Check wiring and repair or replace.
Compressor motor burned out, seized, or
internal overload open
Replace compressor and determine cause.
Defective run capacitor Determine cause and replace.
Compressor cycle (other than
normally satisfying thermostat).
Refrigerant over or under charged Blow refrigerant, evacuate system, and recharge.
Defective compressor Replace and determine cause.
Low line voltage Determine cause and correct.
Blocked condenser Determine cause and correct.
Defective run capacitor Determine cause and replace.
Defective thermostat Replace thermostat.
Faulty condenser fan motor or capacitor Replace.
Restriction in refrigerant system Locate restriction and remove.
Compressor operates
continuously.
Unit undersized for load Decrease load or increase unit size.
Thermostat set too low ♦Reset thermostat.
Low refrigerant change Locate leak; repair and recharge.
Leaking valves in compressor Replace compressor.
Air in system Blow refrigerant, evacuate system, and recharge.
Condenser coil dirty or restricted Clean coil or remove restriction.
Excessive head pressure
Dirty condenser coil Clean coil.
Refrigerant overcharged Purge excess refrigerant.
Air in system Blow refrigerant, evacuate system, and recharge.
Condenser air restricted or air short-cycling Eliminate cause.
Head pressure too low
Low refrigerant charge Check for leaks; repair and recharge.
Compressor valves leaking Replace compressor.
Restriction in liquid tube Remove restriction.
Excessive suction pressure
High heat load Check for source and eliminate.
Compressor valves leaking Replace compressor.
Refrigerant overcharged Purge excess refrigerant.
Suction pressure too low
Low refrigerant charge Check for leaks: repair and recharge.
Metering device or low side restricted Remove source of restriction.
Low evaporator air Increase air.
Temperature too low in conditioned area ♦Reset thermostat.
♦Thermostat should be set between 72° and78°F.
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