Carrier 30RB-170R, Installation, Operation And Maintenance Instructions

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11 - MAIN COMPONENTS OF THE UNIT AND OPERATING CHARACTERISTICS
11.1 - Compressors
The units use hermetic scroll compressors.
Each compressor is equipped as standard with a crankcase oil
heater, and with a head heater for certain configurations.
There is no heater fault detection.
Each compressor sub-function is equipped with:
-Anti-vibration mountings between the unit chassis and the
chassis of the compressor sub-assembly,
-A safety pressure switch on the discharge line of each circuit,
-Pressure and temperature sensors at the common suction
line and a pressure sensor at the common discharge line.
- A suction shut-off valve (for 30RQ/RQP units)
- Restrictors (not visible) on certain suction pipes, to ensure
oil level equalisation between all compressors,
11.2 - Lubricant
The compressors installed on the units have an oil charge,
ensuring good lubrication under all operating conditions.
The oil level check can be done:
-On the system: the oil levels must be greater than or equal to
half of the sight glass.
-A few minutes after the sub-function has come to a complete
stop: the oil levels must be visible in the sight glasses.
If this is not the case, there might be a leak or an oil trap in the
circuit.
If there is an oil leak, find and repair it, then refill with refrigerant
and oil.
See the Service Guide for the oil removal and refill procedures.
IMPORTANT: Too much oil in the circuit can cause the unit
to malfunction.
NOTE:
Only use oils which have been approved for the compressors.
Never use used oil or oil which has been exposed to air.
IMPORTANT: Polyolester oils are completely incompatible
with mineral oils.
Only use the oils specified by the manufacturer.
11.3 - Air-cooled exchanger
30RB/RBP units are equipped with all-aluminium micro-channel
coils (MCHE).
30RQ/RQP units are equipped with coils with aluminium fins
crimped onto internally grooved copper tubes (RTPF).
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