DE DIETRICH ROE-II _ ROE-H - Manual (Page 5)

5
13/01/2011 - 300019360-001-I ROE-II / ROE-H
3 Description
3.1 Safety devices
The aim of the safety devices is to shut down operation of the
machine when it is required outside its normal field of use.
„ High pressure safety
This device, located between the compressor and the condenser, is
a manual reset device. It is preset by the constructor and its action is
signalled on the control panel.
„ Temperature limiter thermostat on the condenser
This thermostat is used only to call on the HP safety device as a last
recourse and to limit the condenser outlet temperature. It is located
slightly below the HP and allows automatic restart of the Heat Pump
after the return to normal operating conditions. This thermostat is
integrated into the heat pump at the condenser outlet.
„
Low pressure safety
The heat pump is fitted with an LP pressure switch with timed switch
and manual reset. It is used to prevent operation with a lack of flow
rate on the evaporator. It is also used to signal any lack of refrigerant
load before excessive overheating and damage to the compressor
occur.
„
Anti-short cycle and compressor start-up
The heat Pump is fitted with a device which prevents all short cycles
on the heat pump. This function guarantees a minimum compressor
shutdown time in the order of 5 to 10 minutes or a maximum number
of compressor start-ups in the hour.
„ Minimum flow rate safety (reversible appliance)
A device prevents operation of the heat pump if the flow rate is
insufficient in the evaporator in cooling mode.
„ Defrosting
During the defrosting cycle, water vapour may appear at
the outside module.