OK now its my turn with a question, I`ve ran across a gas furnace (older Bard) that's about 20 years old. Someone removed the fan center that was in it for running a/c /ga heat changeover. Wire for wire how do I reinstall a new fan center,, it has 3 wires coming from the relay and 2 from the transformer,, with r-g-w-y-c,post on transformwe

I don't understand what you mean by "Fan Center" so if you will describe this a little better maybe I can help.

It sounds like you are wanting to know how to change from heat to AC or visa -versa, is that correct.

Letmetellu:

You must be too young. Fan centers contain a contactor and a 24 VAC transformer.

wmproop:

Here are a bunch of them and instructions from honeywell.
You should be able to handle it.

What colors are the 5 wires?

what colors are the 5 wires?


From the relay, red,brown,black
From the transformer black and white, I`m guessing these 2 go to the 120 volt main hot wire

I don't understand what you mean by "Fan Center" so if you will describe this a little better maybe I can help.

It sounds like you are wanting to know how to change from heat to AC or visa -versa, is that correct.

Yes fan center,is all I know to call it, (thats what they called it at the parts house)
It has a step-down transformer with post for where the tstat wires are to be connected,, and a relay with 3 wires comeing from it that go to fan limit and 2 other places . What I`m asking is which of the 3 wires go where

Letmetellu:

You must be too young. Fan centers contain a contactor and a 24 VAC transformer.

wmproop:

Here are a bunch of them and instructions from honeywell.
You should be able to handle it.


To young?, what they sold me is a 24vac transformer and a relay mounted to a plate,, 2 wire for transformer ,I can figure out.but the 3 wires for the relay/you call it a contactor ,I don`t know where they go

You say here are a bunch of them,, where? I don`t seem to see them

I do know what you are talking about now, the transformer has a terminal board attached to it.

If the terminals are index with a letter such as C, R,W, G, Y. The C terminal goes to the limit and then on to one side of the gas valve. The R goes to the thermostat. The W goes to the other side of the gas valve.

If you have AC on the furnace one wire from the condensing unit goes on C and the other wire goes on Y. Now the wires from the thermostat also go to these terminals G at the thermostat goes to G on the terminal. White on the thermostat goes to W on the W on the terminal and Y from the thermostat goes to Y on the terminal.

I hope this helps you and does not confuse you as much as it has me.

OK, so you have RED, brn and black on the relay. Actually there probably is 2 low voltage wires going there two.

You never said whether you got the primary covered on the Fan Center. I hope you did.

So at this point, you have the tstat wires and the primary connected. Right?

If you have to, you can figure out the hard way what the wires go to.

I forgot to give you a link. Stupid me. http://customer.honeywell.com/techlit/pdf/PackedLit/69-0482.pdf

That should answer all your questions.

Sorry.