Should the Heat/B LED always be on?

[mzcarey]

I have just set up a system with a UT-3000 and two zones, one zone with a communicating Climate Talk thermostat and one zone with a 24 volt thermostat. It seems to be working fine. However, the Heat/B LED is always on, even when neither thermostat is running and the system is not running. Should I be concerned about that, or is it normal (for example is it just saying the heat pump heat/cool terminal is saying heat mode)? Thanks!

[Paul Z.]

The "B" light is always on when system is in heat pump with a "O" valve. When you go to A/C light will drop out.

[waleed333]

just hook the two terminals on the ERV to the two terminals on the control. I have tried hooking each of the ERV control terminals to the Dry Relay on the UT-3000. Do I need to do relay isolation here because the ERV is powered by its own transformer? That is, do I need to drive a separate relay with the ERV control, and hook the terminals of the relay to R and Dry R in Zone 1 on the UT-3000? Thanks!

[Paul Z.]

That tells me that you have a heat pump with an (O) reversing valve. When O is energized B is de-energized, when O is de-energized B is on. It is OK.