How do I check if the thermostat is unable to communicate with its relay module (WM500)?
There are two ways to identify if a relay module is unable to communicate with its thermostat:
- On the thermostat’s display an X in the upper right hand corner.
- You receive a notification on your Pelican web-app stating: “Thermostat Name (Serial No: XXX-XXXX) Check Wiring Module.
From the app, you can also navigate to the thermostat’s configuration page, scroll to the bottom and select Signal Outputs: if you see an X next to Relay Wiring Module (under Communication Status) then the thermostat is unable to communicate with its relay module. This will turn to a check mark when communication is restored.
IMPORTANT: A relay module unable to communicate with its thermostat does not mean the thermostat or relay module are bad.
Troubleshooting a thermostat communication issue with its relay module (WM500):
Here are the steps to take to fix the communication issue:
- Confirm that the correct wires between the relay module and the thermostat are connected. (R) must go to (R). (C) must go to (C). And (D) must go to (D). Note: The thermostat may power on if (R) and (C) were wired backwards, but the thermostat will not be able to communicate with its relay module.
- Verify that the (R), (C), and (D) terminal blocks are making good connection with their wires.
- Check the relay module’s light. If it is flashing (blinking quickly), there is a communication issue. It should be Off for short periods of time and only blink every once in a while (the random blink indicates active communication between the relay module and the thermostat).
- Check that there is at least 21 Vac between (R) and (C) at the thermostat and the relay module.
- Make sure there are no Z8s or Z24s wired to the (D) wire from the thermostat to the relay module. A thermostat should NEVER wired to a Z8 or Z24.
- If you are still having problems, recheck your wires.
- If you are still having problems, contact Pelican Technical Support for further assistance.