EarthLinked Technologies Prime-025, Быстрый старт

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PSD-QS (02/16) Page 49
2) System
Problem /
Symptom Likely Cause(s) Correction
A. System does not
run.
Note: Some digital
thermostats have
a built-in five-
minute time
delay
.
1. Thermostat fault.
1. Adjust thermostat settings. / Replace
thermostat.
2. Power supply problem (AHU /
compressor unit).
2. Check power supply for adequate
phase and voltage. Check wiring to
system and external breakers or fuses.
3. Control voltage problem.
3. Check for 24V on terminal strip
between “R” and “C”.
4. Shut off by external thermostat or
thermostat is defective.
4. Check operation of thermostat.
5. System off on high pressure / low
pressure switches or discharge
temperature switch.
5. Reset limit switch. Analyze system for
root cause.
6. Internal component or connection
failure.
6. Check for loose wiring. Check
components for failure.
7. Compressor contactor not pulling in.
7. Check for 24V across contactor. Trace
24V circuit and components between
“Y” and “C” to locate fault. Repair or
replace as necessary.
8. Faulty run capacitor or start
components.
8. Test each and replace as necessary.
9. Compressor windings shorted or
grounded.
9. See compressor diagram/ replace the
compressor.
B. System runs for
long period or
continuously.
1. Thermostat fault.
1. Adjust thermostat settings / Replace
thermostat.
2. Refrigerant undercharged.
2. Repair leak. Evacuate and recharge
system.
3. Component failure (cooling mode).
3. Check pressures and electrical circuits
for abnormalities.
4. Outdoor thermostat not connected or
failed (heating mode).
4. Check outdoor thermostat and electric
supplemental heat operation. Confirm
proper wiring.
5. Reduced air flow.
5. Check air ducts for leaks and repair.
Check blower operation. Check air
filter(s). Remove air flow restrictions
(min.400 CFM/ton).
6. Four-way valve is short circuiting
refrigerant and bypassing hot gas to
suction.
6. Replace four-way valve, evacuate,
recharge and start-up system.
7. Unit undersized.
7. Contact ETI Technical Support at 863-
701-0096.
C. System blows
fuses or trips
circuit breaker.
1. Inadequate circuit ampacity.
1. Note electrical requirement and correct
as necessary.
2. Short, loose or improper connection
in field wiring.
2. Check field wiring for problems.
3. Internal short circuit. Loose or
improper connection in system.
3. Check wiring in system. See
appropriate wiring schematics and
diagrams. Test components, especially
the compressor, for shorts and grounds.
Figure 36. System Troubleshooting Chart