Schreiber Chillers 1055 New - Manual (Page 27)

Each refrigeration system is mounted on a galvanized steel skid, and is completely self contained. It
contains the following:
High Pressure Switch
The high pressure switch is a manually resetting, totally encapsulated switch that is mounted on a
Schrader valve connection. If the switch requires replacement it can be unscrewed from the piping
system without loss of refrigerant. In the event of a high pressure switch failure, the switch must be
manually reset by pressing the red button. It will close when the system head pressure is below the
switch cut-in pressure. The controller must then be reset.
Low Pressure Switch
The low pressure switch is a automatically resetting, totally encapsulated switch that is mounted on
a Schrader valve connection. If the switch requires replacement it can be unscrewed from the piping
system without loss of refrigerant.
When the suction pressure drop below the cut out value, the compressor will shut off after a short
time delay. At compressor startup there is a starting time delay that ignores and open low pressure
switch to allow suction pressure to be built up. If the suction pressure does not build up fast enough,
the time delay can be increased.