How to control the furnace fan from a secondary thermostat

boilerfurnacethermostat

I have a WaterFurnace geothermal system with upper and lower level zones. I recently added an outdoor wood burner and my issue is that I want to use a secondary stat to run the furnace fan during the heating season. I was hoping that I can easily wire this to my furnace stat but that hasn't been the case.

When I piggyback the red and white wire from the heat only stat to the red and green on the furnace stat, I get a flashing E1 code and nothing works. If I remove the red and green from the stat and tie them together, the fan will not come on. Any thoughts would be greatly appreciated. Thank you.

Best Answer

E1 on waterfurnace I think is a stat wire connection problem. Which makes sense. enter image description here It sounds like you want a space heating wood burner heat to be circulated by your waterfurnace if that's the case this is how your setup should look. If it's an add-on wood burner that ties to the duct or uses its own electrical, that's a whole different approach. I can help with that too if needed.