AirSource CustomAir Installation, Operation & Maintenance Instructions Manual - Page 17
Browse online or download pdf Installation, Operation & Maintenance Instructions Manual for Air Handlers AirSource CustomAir. AirSource CustomAir 20 pages. Air handling units, airsource heatpumps
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Refrigeration Circuits
4 Monthly Checks
Annual Checks
FAULT FINDING
Fault
Unit not operating.
No Supply or Extract fans
running.
No air volume.
Low air volume, fans
Running, airflow fail on.
At every service visit the following checks should be carried out: - Check the
suction and discharge pressures using a service gauge manifold and compare
them with the commissioning sheet. If there is any significant variation, then the
fault should be found and corrected. Refer to the troubleshooting chart. If on
inspection of the refrigeration pressures a refrigerant leak is suspected, open all
access panels to ensure the gas has dissipated to atmosphere.
Visually examine pipework and components for damage, wear and tear and oil
patches, the latter being indicative of a system leak.
Check that the high and low pressure switches are cutting out the compressors
at the correct settings.
High pressure switch cut-out 320psi
Low pressure switch cut-out 30psi
Low pressure switch cut-in 50psi
The gauges can then be removed from the system. Do not forget to replace
the security caps on the Schrader valves.
Check all electrical connections for tightness.
Check all refrigeration connections with a foam or detergent leak detector.
Possible Cause
No power to unit.
Fire link open.
Defective damper end switch.
No power to fans
Fan drive or motor failure
Filters blocked
Incoming phases crossed.
Remedy / Action
Check mains supply and main AHU isolator.
Inspect fireman's panel.
Check actuator operation and end switch
making when open.
Check control switch, fuses, MCB's and
control circuit wiring.
Inspect drive belts when applicable. Check
motor winding resistance.
Remove packaging or replace.
Check fan rotation. If incorrect change mains
incoming phases over. Not individual fans.
Installation, Operation & Maintenance Manual
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