Boiler and an old oil furnace with nest

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New Member
Jan 5, 2022
Hey guys, I'm a new OWB owner, excited to start my journey!

I just got the boiler filled, Wood master 4400, water is circulating and fire is burning. While I'm waiting for the water to heat I'm working on my thermostat situation and I'm at a loss.

I have an old Thermo Pride two-wire oil furnace. Attached pictures are labeled.

Currently when I have a call for heat the oil furnace fires like normal and when it detects its up to temperature and the plenum it sends power to the fan. Currently only the red and white wires for the thermostat wiring are used, connected to RH and W1.

Since I don't have the boiler system water up to temperature yet I can't give it a proper test, but I'm concerned it is not going to work how I want it to and only turn on the fan when I have a call for heat. How can I make this work?

I've been watching a bunch of videos but I can't find one that the same situation. I would love any help, I'm happy to answer any questions.

Thanks in advance!

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