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[RSI]

Assuming I read the schematic right, is there any reason you couldn't cut the orange wire from the burner junction box and connect the control side to the common in the ranco, the other end of it to the NO connection and run a wire from the NC to splice in with the red blower motor wire? This would be assuming you are using the ranco on cooling mode. If using heating mode you would need to swap wires on NO and NC.

[MaverickM23]

I have attached two photos of my furnace wiring diagram. Its similar to the one on the link I posted. Just trying to see which wire I need to break. Also I was looking at the wiring diagram for the Ranco and I understand breaking the hot line to the burner but what wire would I use for the COM on the upper terminal in the Ranco? If Im just breaking the one wire do I need a COM for it to function properly? One again thanks for all the help.

[hondaracer2oo4]

Yes you need a neutral wire to the ranco. Unlike a mechanical thermostat it needs power to run the thermostat.

[MaverickM23]

So I assume I can get the neutral from anywhere like the white wire that runs to the fan. Looking at the picture I took do you still think I should break the  B wire in the burner mounted junction box?

[hondaracer2oo4]

Yes you can grab the nuetral wire from anywhere as long as it's on the same circuit that you are breaking the hot wire from. RSI knows better than I do but I figured killing the whole burner down below would be easiest.

[RSI]

What I suggested should turn the blower on instead of the burner when the thermostat calls for heat. The Ranco would divert the power that runs the burner to the fan. When the OWB temp dropped then it would switch back to normal.

If doing it this way, you would want to make sure the blower motor didn't draw more current than the burner control is rated for or use a relay to handle the load.

[MaverickM23]

Is there anyway I could get you to do a drawing for me I'm still a little confused on how this should be wired up. I tried drawing it myself but not sure where to break the orange and how to wire up the ranco. Thanks in advance

[RSI]

First of all, we should make sure we are all talking about the same thing before it gets confusing. I am not sure if I missed something but I didn't see how you were going to actually make the fan run if you have the Ranco break the B wire. If you have that already figured out, can you post that again. I mentioned using the orange wire because that is probably going to work best if you don't use any other relay.

[RSI]

I just realized that what I suggested may not work due to the flame sensor shutting it down the burner control.

I think you will need another relay to be able to get everything to work correctly.

[MaverickM23]

What I'm trying to do is to get the Ranco to kill the power to the burner only but keep the power to the fan when the thermostat in the house calls for heat. I figured I would use the Ranco to to break it on a temperature rise so once the loop is say 140 it wold break power to the burner, and if it ever dropped below 140 the ranco would make the connection again and the oil burner would fire.

[hondaracer2oo4]

Your still going to need a relay to turn on the fan.

[MaverickM23]

So what would the wiring for that look like? Couldn't I break and use the orange and the white going to the oil burner and wire them into the aquastat? Im guessing I would break them after the transformer but not sure if that would work. Any ideas?

[RSI]

When I posted the other night it was late and I forgot about the burner control needing to see fire to run.
If you use the orange wire like I suggested, it would run the fan for a few seconds and then shut off because there was no light picked up by the flame sensor.

You will be best off adding another relay. Since there is no usable 24v transformer on the furnace, you would be best off to use a fan center relay or switching relay.

[MaverickM23]

So what would that look like with my wiring and would I still be using the aqua stat? It came today and I was gonna start working on it tonite or tomorrow

[RSI]

Yes, you would still need it if you want to use a single thermostat.
I think you will want to get a 2 pole fan center.
How it gets wired will depend on how you want it to work. It would be easiest to just wire it up so the fan always ran when the thermostat was calling for heat. This would over ride the existing fan control that only runs the fan when the plenum is hot. If you don't want to do that, you will need to setup the ranco to divert the power from the B wire to the fan wire when the OWB is hot.

We can tell you how to wire it once we know more how you want it to work.