Outdoor Wood Furnace Info

All-Purpose OWF Discussions => Electronics => Topic started by: Corngrinder on November 24, 2014, 10:39:45 PM

Title: Need advice on t-stat wiring.
Post by: Corngrinder on November 24, 2014, 10:39:45 PM

Hi all,

I've had my boiler up and running for a little over a week now.  The system is functioning beautifully with only 1 minor set back.  The first time my secondary thermostat called for heat, it also turned my A/C on.  Any quick ideas on how to rectify?

I have the basic double thermostat set-up for an existing forced air unit using the guide CentralBoiler has on their website.  I've been working 12 hours since the install and haven't had much time to troubleshoot... any advice would be appreciated so I can get it done sooner rather than later.  Currently, I have the breaker disconnected for the A/C unit - that was my quick-fix.

Title: Re: Need advice on t-stat wiring.
Post by: slimjim on November 25, 2014, 03:27:12 AM

I'd love to help but I use a single TT and add an Aqua stat to kill all but the blower on the backup system, I think RSI has your solution!

Title: Re: Need advice on t-stat wiring.
Post by: RSI on November 25, 2014, 10:18:51 PM

The quick fix is to remove the wire off the G terminal on the original thermostat and only run it to the W in the second thermostat. This is assuming you have a gas furnace. If you have a heatpump you may need to add a relay.

Another possible thing that might work but I haven't gotten around to trying out yet, use the original thermostat for the OWB and the 2nd for the backup heat. To do this, take the wire off the W terminal and run it to the W in the new thermostat. Then add a jumper from the G to the W on the original thermostat. You will still need the RH and c jumpers between the two thermostats.

Not sure if the 2nd way will work but I think it should.

Title: Re: Need advice on t-stat wiring.
Post by: Corngrinder on November 25, 2014, 10:49:33 PM

Thanks, RSI.

I have a gas furnace as back-up.  When I remove the 'g' terminal from the original thermostat, will I have to reconnect it during the summer months when I want the A/C to run?  Or, is this a permanent fix?

Title: Re: Need advice on t-stat wiring.
Post by: RSI on November 25, 2014, 10:50:42 PM

You probably won't have to connect it again. I always just leave them off.