Carrier VECTOR 1800 MT, Operation & Service Manual

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62-11039 7-19
Alarm
NO.
Steps ALARM / CAUSE CORRECTIVE ACTION
28 CHECK REFRIGERATION SYSTEM
•
TRIGGER ON: The refrigeration system is running and the discharge pressure is less than 5 PSIG
(0.34 Bar) higher than suction pressure for more than 10 minutes
•
UNIT CONTROL: Engine operation: alarm only or (if configured for shutdown) engine and unit shutdown
and alarm. Standby operation: alarm only or (if configured for shutdown) refrigeration system shutdown
and alarm with PSCON still energized.
•
RESET CONDITION: Auto reset when discharge pressure is more than 20 PSIG (1.36 Bars) above the
suction pressure when in alarm only, or auto reset after 15 minutes when shutdown is configured or alarm
may be manually reset via keypad or by turning the unit off, then back on again.
NOTE: Follow the steps below until a problem is found. Once a repair or correction has been made, the active alarm
should clear itself (see reset condition above). Operate the unit through the appropriate modes to see if any active
alarm occurs. Continue with the steps below as necessary.
1. Verify Compressor Is Running.
a. Check compressor Amp draw -- CCON
T1--T2, T1--T3, T2--T3.
2. Check System Pressures
a. Install Manifold Test Set and check and
compare compressor discharge &
suction pressures with those shown on
the microprocessor controller.
Suction pressure must be above 3 PSIG (0.2 Bar)
Suction & Discharge Pressures must have the same
reading on gauges & on micro display.
NOTE: Microprocessor suction pressure reading has
a maximum value of 100 psig (7.5 bar)
3. Perform Pre--trip Check
a. Run pre--trip & check for alarms Any active alarms must be corrected and cleared before
proceeding.
4. Check Compressor.
a. Perform Pump--Down Test.
See Section 8.10.1
Must pump down to 5 PSI and hold for minimum of 1
minute.
b. Cover condenser and build--up
discharge pressure.
Must be able to pump up to 400 PSI.
c. Disassemble and inspect compressor
valve plates, reeds, pistons, etc.
Must be intact, clean, and in good working order.