Process (Steps 1-30):
1. Place the unit in to test mode.
2. Does the compressor run in test mode? If yes continue on to the next step, if no go to step 16.
3. Is the unit BAS controlled? If yes continue on to the next step, if no go to step 10.
4. Disconnect/bypass connection to communications card in unit.
5. Disconnect Zone sensor.
6. Jump R to Y1 on RTRM (or Y1/Y2 with respect to problem compressor).
7. Did the compressor run? If yes continue on to the next step, if no go to step 9.
8. Troubleshooting of the BAS is required. Jump to end.
9. Verify RTRM functionality – replace if necessary. Jump to end.
10. Disconnect all thermostat/zone sensor wires and jump R to Y1 on RTRM(or Y1/Y2 with respect to problem compressor).
11. Did the compressor run? If yes continue on to the next step, if no go to step 15.
12. Verify thermostat/zone sensor function, programming, and wiring.
13. If thermostat verify there is no bleed voltage on the other control inputs.
14. Replace thermostat/zone sensor if necessary. Jump to end.
15. Verify RTRM functionality – replace if necessary. Jump to end.
16. Is the contactor pulling in? If yes continue on to the next step, if no go to step 20.
17. Is the compressor seeing proper voltage on all three phases? If yes continue on to the next step, if no go to step 19.
18. Check compressor for open winding, locked rotor, etc. Jump to end.
19. Check for blown fuses, loose wiring, etc. Jump to end.
20. Is the LPC or HPC open? If yes continue on to the next step, if no go to step 22.
21. Verify unit pressure/charge and pressure cutouts. Jump to end.
22. Is the compressor relay output active on the RTRM? If yes continue on to the next step, if no go to step 27.
23. Is there 20-26 VAC present on the low voltage wiring? If yes continue on to the next step, if no go to step 25.
24. Replace the Compressor Contactor. Jump to end.
25. Check for proper Voltage setup on the 24 VAC transformer.
26. Check wiring connections. Jump to end.
27. Is the frostat open on the RTOM? If yes continue on to the next step, if no go to step 29.
28. Verify frostat functionality – replace if necessary. Jump to end.
29. Verify RTRM functionality – replace if necessary.
30. End.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.