Cooper & Hunter CHV-5S224SNMX, Service Manual

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0 79 MAINTENACE
CHV
5 COM PACT MULTI VRF UNIT
SERVICE M ANUAL
2.3 Low-Pressure Protection
Low-pressure protection
Use pressure gauge to measure if the pressure
is really low?
Check if the refrigerant in the system is too
low?
Check if the operation mode of indoor unit is
set properly?
Check if the gas valve and liquid valve of
outdoor unit are fully open?
Check if the front panel of outdoor unit is
covered tightly?
Check if the air inlet and outlet of the indoor
and outdoor exchanger is smooth?
Check if the indoor and outdoor fans run
normally?
Check if the indoor swing louver is fully
open?
Check if the capacity output of outdoor unit
is equal to the capacity demand of indoor
units?
Check if the indoor electronic expansion
valve can work normally
Check if the indoor / outdoor filters or
radiating fins are dirty or blocked?
The system pipe is blocked
Refer to low pressure sensor error
Add refrigerant according to the nominal
refrigerant volume on nameplate and the
calculated charge volume
Refer to the Instruction Manual for Indoor
Unit
Fully open the valve
Cover up the front panel properly
Remove the obstructions
Measure the fan motor and signal input
Measure the swing motor and signal input
Refer to the dial-up of indoor and outdoor
unit
Engage the valve body with the coil
Refer to the Repair and Maintenance
Focus on checking the inlet and outlet of the connection between indoor units and
main pipe. Also focus on checking the electronic expansion valve of indoor unit and
outdoor unit. Replace the electronic expansion valve, drying filter and other parts
NO
YES
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YES
YES
YES
YES
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YES
YES
YES
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YES
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YES
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NO