Schreiber Chillers 15MEDAC email - Manual (Page 53)

Servicing refrigeration and air conditioning systems can be dangerous, and the personnel servicing such
equipment should exercise extreme caution in all respects. The precautions discussed in this bulletin
deal only with those dangers associated with VENTING TERMINALS.
CRANK CASE HEATERS
This unit has a CRANK CASE HEATER on the compressor. It is important to the life of this compressor
that you follow the instructions. This low wattage heater protects the compressor when it is idle by
producing just enough heat to keep the Freon from accumulating in the compressor. Under certain
specific conditions this heater will prevent the compressor from slugging causing damage to its internal
parts.
These Heaters were wired at our factory in such a way that allows the heater to be on any time the
disconnect switch on the chiller is on. When you want to turn the water pump or refrigeration compressor
off, you must only use the manual switches on the electrical enclosure as marked. When you use the
disconnect to turn the unit off you kill the power to the crank case heaters. ONLY use the disconnect to
turn off power if you are going to work on the electrical system.
AN IMPORTANT FACTOR- READ
SPECIAL INSTRUCTIONS FOR CRANK CASE HEATER
When the unit is first received, the power to the chiller should be on for 3 hours. That means you must at
this time have the unit disconnect on. The manual water pump and refrigeration switches should be off.
This will allow the refrigeration compressor to warm up, driving out the Freon (R22) that had migrated to
the compressor.
The crank case heater is HIGH VOLTAGE. But it is only very low wattage. Caution should be taken
when working on the crank case heater to make sure the POWER is off.
Any question call for more details at Schreiber Engineering 562-926-3855.