BEACON CONTROLLER
20
PROBLEM POSSIBLE CAUSE POSSIBLE CORRECTIVE ACTION
Beacon Board Status 1. Supply voltage too high 1. Check 24 volt supply; if above 30 volt
Light Flashes Erratically correct immediately.
2. Supply voltage too low 2. Change transformer primary to correct supply
3. Bad board voltage tap. 208 or 240 volts.
SERVICE DIAGNOSIS CHART -
BEACON

(cont’d.)

PROBLEM POSSIBLE CAUSE POSSIBLE CORRECTIVE ACTION
Compressor will not run 1. Fused disconnect switch is open 1. Close switch
2. Blown Fuse 2. Check reason fuse is blown; replace fuse
after problem is corrected.
3. Compressor motor protector open 3 . Motor protector is automatic reset; allow
time for compressor to cool down so that
protector will reset; check unit for reason
when compressor restarts.
4. Defective compressor contactor 4. Replace
or holding coil
5. Open room air sensor (air into coil) 5. Check room air sensor; if open, replace. After
reconnecting, wait 4 mins. for compressor to
restart.
6. Compressor discharge too hot 6. Lower evaporator superheat to lower
compressor suction gas temperature
7. Open low pressure, high pressure 7. Check control settings
or oil safety control
8. Motor problems 8. Check motor for open circuit, short circuit,
grounded windings or burn-out
9. Loose wiring 9. Check all wire terminals; tighten if necessary
Compressor noisy or 1. Flooding of liquid refrigerant into 1. Check expansion valve superheat setting
vibrating into crankcase on control board
2. Compressor hold-down nuts too 2. Loosen compressor hold-down nuts until
tight or too loose compressor floats freely on mounting springs
3. Worn compressor/bad valves 3. Replace
High head pressure 1. Too much refrigerant 1. Remove excess refrigerant
2. Non-condensables in the system 2. Purge system of non-condensables
3. Dirty condenser coil 3. Clean condenser coil
4. Condenser fan not running 4. Check electrical circuit, including fuses
5. Discharge valve partially closed 5. Open valve
6. System running beyond condensing
temperatures due to heavy load
or out of equipment design paramaters
Low head pressure 1. Insufficient refrigerant 1. Check system for leaks; repair leaks &
add refrigerant
2. Damaged valves in compressor 2. Replace compressor
3. Winter operation w/o head 3. Check refrigerant charge
pressure valve
High suction pressure 1. Expansion valve over-feeding 1. Check expansion valve superheat setting
on control board
2. High box temp. pull-down 2. Wait for box temp. to drop
3. System undersized 3. Check load & design criteria

SERVICE DIAGNOSIS CHART -

GENERAL