Lennox MCC Series, Инструкция по установке, эксплуатации и обслуживанию

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Installation - Operation - Maintenance manual (IOM) • AIR COOLED CHILLERS & SPLIT UNITS - 1106-E
• 18 •
Ensure conduct liquid line and gas line pressure tests are in conformity with applicable legislation. Before starting up
a unit on a receiver, the piping and the condenser must be dehydrated. Dehydration should be carried out using a
double stage vacuum pump, capable of drawing 600Pa absolute pressure vacuum.
Best results are obtained with a vacuum down to 100 Pa. To get down to this level at normal temperatures, i.e.
15 °C, it is often necessary to leave the pump running for 10 to 20 hours. The duration of pump operation is not a
factor of efficiency. The pressure level must be checked before the unit is put into service.
3.7.5 - Refrigerant charge
Chillers with R407C must be filled in the liquid phase. Never charge a machine operating on R407C in the vapour
phase (vapour): the composition of the mixture could be modified.
In liquid phase, connect either to a liquid isolating valve, or to the quick-connector on the liquid line at the valve outlet.
For unit using R22, the charging may be done in vapour phase in that case, connection will be made to the suction
valve.
Note:
Splits units are supplied with a refrigerant or nitrogen holding charge. Before pulling down the vacuum for
dehydration, completely purge the unit.
Charge the unit until there is a constant flow of bubble-free liquid in the sight-glass indicating that there is sufficient
charge and controlled that sub cooling is correct according to the system design value.
In all cases, do not top up the charge until the unit reaches a stable state of operation.
It is pointless to overcharge a system, this can adversely affect operation.
Overcharging causes :
- Excessive discharge pressure,
- A risk of damage to the compressor,
- Excessive power consumption.
3.7.6 - Oil charge
All units are delivered with a complete oil charge. In the case of split units, it may be necessary, due to the length of
piping installed, to add a certain amount of oil compatible with the type of compressor and refrigerant used.
Please refer to the following oil table.
Note : This table is valid for self-contained chillers only (or chillers mounted on receivers) on which the
leaving water temperature is not lower than -5°C. For other cases, consult the documentation shipped with
the machine.
Oil recommendation for Lennox chillers
Refrigerant Compressor type Brand Oil type
R22 Screw CSH… Bitzer B320SH
R22 Scroll SM… Maneurop Maneurop 160 P
R22 Scroll ZR… Copeland Suniso 3 GS
R22 Reciprocating D8… Copeland Suniso 160P
R22 Reciprocating MT… Maneurop Maneurop 160 P
R407C Screw CSH… Bitzer BSE170
R407C Scroll SZ… Maneurop Maneurop 160 SZ
R407C Scroll ZR… Copeland
Copeland 3MA, Mobil EAL,
Arctic 22CC, ICI Emkarate,
RL32CF
R407C Reciprocating D8… Copeland Mobil EAL Arctic 22
R407C Reciprocating MS… Maneurop Maneurop 160 SZ