Specifications
46
During transport in a closed container the refrigerant charge
must be transferred to the condenser. This prevents that
the pressure in the evaporator reaches the valve calibration
pressure during transport (if this happened, the charge
would be evacuated to the atmosphere and the unit would
be empty when it arrives on site).
For this reason the charge is transferred to and stored in
the condenser, and the liquid and discharge line valves are
closed.
The following precautions must be taken during installation:
• Ensure that there is sufficient water flow in the
evaporator.
• Energise the unit.
• Open the liquid line valves.
• Open the EXV to return the charge to the evaporator;
pressure equalisation must be verified by a quick test
procedure.
• Open the discharge line valve.
30RB units use hermetic scroll compressors.
Each compressor is equipped with a crankcase oil heater,
as standard, complete with a safety device that prevents
compressor start-up if there is a fault at the heater.
As standard, each compressor is equipped with a discharge
valve. As an option each compressor can be equipped with
a suction valve (option No. 92).
Each compressor sub-function is equipped with:
• Anti-vibration mountings between the unit chassis
and the chassis of the compressor sub-function.
• Suction piping equipped with openings (not visible) to
ensure an even oil level between all compressors.
• A non-return valve at the discharge of all compressors.
• A pressure safety switch at the discharge of all compres-
sors, located between the compressor and the valve.
The compressors installed in these units have an oil charge
of 6.7 l to ensure their correct operation.
The oil level check must be done with the unit switched off,
when then suction and discharge pressures are equalised.
The oil level must not be visible in the sight glass (level
below the sight glass). If this is not the case, there is an oil
leak in the circuit. Search and repair the leak, then recharge
oil, so that it reaches a high sight glass level, when the unit
is recharged with refrigerant. The refrigerant dissolved in
the oil raises the level - do not add any more oil.
ATTENTION: Too much oil in the circuit can cause a
unit defect.
NOTE: Use only oils which have been approved for the
compressors. Never use oils which have been exposed to air.
CAUTION: R-22 oils are absolutely not compatible with
R-410A oils and vice versa.
The 30RB coils are micro-channel condensers made entirely
of aluminium. For some options (see chapter 15 - Options
and Accessories) optional coils with internally grooved
copper tubes with aluminium fins are also available.
The fans are axial Flying Bird fans equipped with rotating
shroud and made of composite recyclable material. Each
motor is fixed with transverse supports. The motors are
three-phase, with permanently lubricated bearings and
insulation class F.