Carrier VECTOR 1800 MT, Руководство по эксплуатации и обслуживанию

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Alarm
NO.
Steps ALARM / CAUSE CORRECTIVE ACTION
55 CHECK DEFROST AIR SWITCH
• TRIGGER–ON: The defrost air switch has called for a defrost cycle within 8 minutes of a defrost
termination for 2 consecutive defrost cycles. (The air switch contact must be closed continuously for
15 seconds before the defrost cycle is started.)
• UNIT CONTROL: Engine and standby operation: alarm only. While this alarm is active, the defrost air UNIT CONTROL: Engine and standby operation: alarm only. While this alarm is active, the defrost air
switch will NOT be used to initiate a defrost cycle; however the Defrost Timer will initiate a defrost cycle
90 minutes after the alarm comes on, and the manual defrost switch will remain operative.
• RESET CONDITION: Auto Reset when defrost cycle terminates correctly, and the air switch does not call
for a defrost cycle within the 8 minutes following defrost termination, 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. Check Defrost Air Switch
a. Inspect switch & connector pins &
terminals
No damaged or corroded pins
b. Check switch setting and resistance of
switch contacts
Refer to Section 2.12
Contacts closed with pressure applied to high side
Contacts open with no pressure applied
2. Check Switch Wiring
a. Inspect harness & control box
connector pins & terminals (See wiring
schematic)
See Note 5
No physical damage to harness.
No damaged or corroded pins
3. Check Air Switch Hoses
a. Inspect air hoses to switch No kinks or other obstructions
No holes
Connected to correct nipple
4. Check Condition Of Evaporator
a. Visually inspect evaporator following
defrost.
Coil must be clean and cleared of ice or any other
material.
5. Perform Pre--Trip
a. Run Pre--Trip and check for alarms. Any active alarms must be corrected and cleared before
proceeding.
6. Check Evaporator Pressure Drop
a. Check pressure reading with
Magnehelic Gauge
Refer to Section 2.12
7. Check Evaporator Contactor
a. Check Evap Fan operation in defrost Must disengage fan.
8. Check Condition Of Trailer Compartment & Load
a. Check condition of trailer compartment
doors & seals
Doors must be closed, and door seals must seal and
prevent outside air from leaking in.
b. Check condition of product. If it is warm
and moist, frequent defrost cycles can
be expected.