16
ENVIRONMENTAL
MANAGEMENT
TROUBLESHOOTING CHART
Below we list a series of possible faults, along with the probable causes and suggested solutions. In the event of a unit
malfunction, it is advisable to disconnect the power supply and ascertain the cause.
SYMPTOMS
CAUSE
REMEDY
Compressor does not run
Compressor stops or cycles rapidly on
low-pressure control
Compressor cycles rapidly on high-
pressure control
Operating cycles too long or continuous
operation
System noises
Compressor loses oil
Frosted or sweating suction line
Hot liquid line
Frosted liquid line
Compressor will not unload
Compressor will not load
Reset circuit breaker
Check control circuit for ground or short; repair and
reset breaker
Reset thermostat
Replace contactor
Check connections
Check wiring and rewire
Check line voltage - determine location of voltage
drop and remedy deficiency
Check motor windings for open or short. Replace
compressor, if necessary
Replace compressor
Check chilled water pump. Check switch.
Raise differential setting. Check capillary for pinches.
Replace control.
Open valve
Add refrigerant
Clean strainer. Clean or replace.
Check capillary tube for pinches. Set control as
required.
Open valve, or replace if defective.
Purge, dehydrate and recharge.
Check motor and wiring. Repair or replace if defective.
Check fan position and security on shaft.
Add refrigerant.
Replace control device concerned
Purge
Clean or replace
Replace or repair
Check valves, replace if necessary.
Support piping as required. Check for loose pipe
connectors.
Add refrigerant. Check for blocked liquid line strainer.
Check valve plates for valve noise. Replace
compressor (worn bearings). Check for loose
compressor hold-down bolts.
Find and repair leak, pump down and recharge.
Replace heaters, check wiring.
Adjust expansion valves.
Repair leak and recharge.
Adjust expansion valve.
Remove restriction or replace filter-drier.
Replace coil.
Replace.
Wire correctly.
Replace.
Replace.
Wire correctly.
Clean.
Power line open
Tripped circuit breaker
Safety thermostat tripped
Contactor stuck open
Loose terminal connection
Improperly wired controls
Low line voltage
Compressor motor defective
Seized compressor
Chilled water flow switch open
Low-pressure control erratic in action
Compressor discharge valve partially closed
Low refrigerant charge
Filter-drier blocked or fouled
High-pressure control erratic in action
Compressor discharge valve partially closed
Air in system
Condenser fan(s) not operating or low air flow
Low refrigerant charge
Control contacts fused
Air in system
Partially blocked or blocked expansion valve or strainer
Defective insulation
Inefficient compressor
Piping vibrations
Expansion valve hissing
Compressor noisy
Leak in system
Crankcase heaters not energizing during shutdown
Expansion valve admitting too much refrigerant
Shortage of refrigerant due to leak
Expansion valve closed too far
Restricted filter-drier
Burnt-out coil
Leaky bypass piston
Miswired solenoid
Weak bypass piston spring
Damaged bypass piston
Miswired solenoid
Blocked bypass port strainer (high side)
Order No. 13811-76, May 1998. Supersedes order No.: 13811-76, September 1996 + 13883-76, April 1995.
Manufactured by: Carrier SA, Montluel, France.
Manufacturer reserves the right to change any product specifications without notice.
Printed on Totally Chlorine-Free Paper.
Printed in the Netherlands.
