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Q)

What refrigerants can Maneuop compressors be used on?

A)

With the correct refrigerant oil Maneurop compressors can operate on CFCs, HCFCs and HFCs.

Q)

Can the Maneurop compressor replace other manufacturers.

A)

Because of their versatility Maneurop compressors can replace many other brands. If you contact us with the model you wish to replace and the application, we will be able to give you the equivalent Maneurop model.

Q)

What is meant by suction gas cooled?

A)

The motor driving the Maneurop compressor relies on the suction gas flowing through it to keep it cool. This results in the compressor running cold to the touch on A/C applications and with ice around the suction connection on freezers.

Q)

If noise is a problem, can the compressors be made quieter?

A)

Yes, because the compressor is suction gas cooled it does not rely on external air for cooling. Therefore we can supply an acoustic hood that fits over the compressor reducing the noise level. For more information about noise levels please contact our Engineering Dept.

Q)

What has caused the compressor to go open circuit on all the windings?

A)

Both 1ph and 3ph compressors are fitted with a star point internal overload. The overload is both temperature and current sensitive. Should the running conditions (e.g. high head pressure) result in a higher drawn current the overload will trip, this may take up to an hour to reset. If the system loses charge to such a point that there is insufficient to cool the motor, again the overload will trip. As the motor may be hot under this condition it could take up to 2 hours to reset.

Q)

What protects the compressor from high discharge pressures?

A)

If the differential pressure inside the compressor reaches an unsafe level an internal relief valve will open. Once the pressures are equalized the valve will close. This can take several minutes. Normally when the internal relief valve opens the internal overload will also trip.

Q)

How much oil should be in the compressor?

A)

Maneurop compressors do NOT need oil pressure differential controls.

Q)

When should oil be added to the system?

A)

The oil level in the sight glass (if fitted) should be ¼ to ½ full when not running, and should be checked after a minimum of 2 hours running. If the system has an oil separator, oil "P" traps or the total run of suction and liquid line exceed 20m, then oil has to be added.

Q)

Can the Maneurop compressors be started Star/Delta?

A)

No, all the 3 phase Maneurop compressors use a D.O.L. (Direct On Line) start. Should the high starting current cause a problem, it can be reduced using a soft start device. Please contact us for details.

Q)

What crankcase heaters are used?

A)

The reason for using a crankcase heater is in case the compressor becomes colder than the evaporator. The refrigerant will boil off from the evaporator and condense in the compressor. On start up the refrigerant in the crankcase that would have mixed with the oil boils violently, foaming the oil. Under these conditions the oil could get carried into the cylinder causing valve or bearing failure. On 1ph compressors there are two heater systems, one uses a PTC heater that plugs into the pocket on the side of the crankcase. This is rated at 30watt and can operate on electrical supply from 200v to 600v. As the heater is self regulating it may be left on all the time. The other system is to use a trickle electrical current through the motor windings. This is a very effective method but requires a permanent power supply to the compressor during the off cycle.

The fact that the PTC heater can operate up to 600v also makes it ideal for the 3ph compressors as the heater can be wired across phases, thus making a neutral power line unnecessary.
As the heater is self regulating it may be left on all the time.
If the compressor is in a position where it can become colder than the evaporator for some time i.e. beer cellars in winter there are wrap round heaters available to give additional heat.