Lennox ASC Series Installation, Operating And Maintenance Manual page 31

4. MAINTENANCE
4.3.1.- SAFETY DEVICES
ASTP COMPRESSOR PROTECTION:
This device protects the compressor against high discharge temperatures.
When the temperature reaches critical values, ASTP protection causes the "Scrolls"
to separate. The compressor stops pumping but the motor continues to run.
- Occasionally, when the compressor stops and starts, there is a metallic noise due to
the compressor scrolls. This is normal.
- Connect high and low pressure gauges and check that the operating pressures are normal.
- Measure electrical consumption for the unit and check that it is close to that indicated on the specifi cation plate.
- Check the electrical consumption of the compressor and the fans against that specifi ed in the physical data sheets.
- In the case of a Heat Pump unit, make a cycle change on the Control Panel, checking that the 4-way valve makes
the change correctly. Check the pressures in the new cycle.
- Split and Multi-split: Low pressure switch and high pressure switch are reset automatically and if it operates
3 times in one day, they change to manual reset, through the control unit.
- With C60 control: Low pressure switch and high pressure switch are reset automatically and if it operates 3
times in one day, they change to manual reset, through the control unit.
• 30 • Installation, Operation and Maintenance manual • ASC/ASH-MIL152E-1217-01/2019
Unit with specifi c compressor protection
La unidad incorpora compresor con protección específi ca