Check out some similar questions!

Lazarwulf · Jan 14, 2007, 04:37 PM

Short summary. If the switch at the Payne gas furnace (from 50's) is on, the blower stays on. Gas seems to light properly with the thermostat. I have replaced both the fan limit control and the limit control (both made by camstat). There are no relays.

This is a definite fixer-upper house, and I have seen some strange things. I am convinced that the wiring is completely wrong. To make matters worse. All wires are black with the exception of the 120v wires coming into the furnace and the blower motor wires.

A summary of how this should be wired would be most helpful.

Instructions like connect the 2 leads from the transformer out to the..
Connect the >>?

List of wires.
I of course have 120v in to the furnace.
120v single pole switch.
24v transformer with 2 wires (both black).
2 thermostat wires.
2 lead Camstat FAL7C 20BT-120-AB fan switch.
2 lead Camstat L59-7B-A limit switch.
2 wire pilot.
2 wire gas switch.
Blower motor with 2 wires (black and a white).

Currently this is how it is wired.
120v black -> 120v single pole switch and
120v white -> blower white and transformer out
120v single pole switch -> black 120v and black blower wire
Thermostat wires -> 1 to transformer nut and 1 to gas switch
Gas switch -> 1 to transformer nut and 1 to pilot
Pilot -> 1 to gas and 1 to transformer
Transformer out -> 1 to 120v white and 1 to Camstat L59-7B-A limit switch C. (right side)
Camstat L59-7B-A limit switch -> 1 to transformer out and 1 to black blower
Camstat FAL7C 20BT-120-AB fan switch -> 1 to 120v black and 1 to black blower
Blower motor -> black connects to single pole switch, Camstat FAL7C 20BT-120-AB, and Camstat L59-7B-A

All this wiring except the obvious exceptions is in a "junction box" built into the furnace.

Damn that took a while to write out :)

-Twain

Lazarwulf · Jan 20, 2007, 06:29 PM

Originally Posted by Lazarwulf

Short summary. If the switch at the Payne gas furnace (from 50's) is on, the blower stays on. Gas seems to light properly with the thermostat. I have replaced both the fan limit control and the limit control (both made by camstat). There are no relays.

This is a definate fixer-upper house, and I have seen some strange things. I am convinced that the wiring is completely wrong. To make matters worse. All wires are black with the exception of the 120v wires coming into the furnace and the blower motor wires.

A summary of how this should be wired would be most helpful.

Instructions like connect the 2 leads from the transformer out to the...?
Connect the >>?

List of wires.
I of course have 120v in to the furnace.
120v single pole switch.
24v transformer with 2 wires (both black).
2 thermostat wires.
2 lead Camstat FAL7C 20BT-120-AB fan switch.
2 lead Camstat L59-7B-A limit switch.
2 wire pilot.
2 wire gas switch.
Blower motor with 2 wires (black and a white).

Currently this is how it is wired.
120v black -> 120v single pole switch and
120v white -> blower white and transformer out
120v single pole switch -> black 120v and black blower wire
Thermostat wires -> 1 to transformer nut and 1 to gas switch
Gas switch -> 1 to transformer nut and 1 to pilot
pilot -> 1 to gas and 1 to transformer
transformer out -> 1 to 120v white and 1 to Camstat L59-7B-A limit switch C. (right side)
Camstat L59-7B-A limit switch -> 1 to transformer out and 1 to black blower
Camstat FAL7C 20BT-120-AB fan switch -> 1 to 120v black and 1 to black blower
Blower motor -> black connects to single pole switch, Camstat FAL7C 20BT-120-AB, and Camstat L59-7B-A

All this wiring except the obvious exceptions is in a "junction box" built into the furnace.

Damn that took a while to write out :)

-Twain

No one willing to tackle this one?

rickdb1 · Jan 20, 2007, 07:38 PM

The safety and control circuits will be wired in series, both line and low voltage.

labman · Jan 20, 2007, 07:42 PM

Sorry your question got missed. I used to answer all the questions here, but lately I have been leaving them for people that know more than I do. Of course some of the answers look to me like others should have left them go too.

120v black -> 120v single pole switch and
Ok
120v white -> blower white and transformer out
Ok
120v single pole switch -> black 120v and black blower wire
The black wire then needs to connect to one lead of the transformer and the line terminal of the fan switch
Thermostat wires -> 1 to transformer nut and 1 to gas switch
Ok
Gas switch -> 1 to transformer nut and 1 to pilot
You are losing me here, the gas switch has 3 wires?
Pilot -> 1 to gas and 1 to transformer
Transformer out -> 1 to 120v white and 1 to Camstat L59-7B-A limit switch C. (right side)
Camstat L59-7B-A limit switch -> 1 to transformer out and 1 to black blower
Camstat FAL7C 20BT-120-AB fan switch -> 1 to 120v black and 1 to black blower
Blower motor -> black connects to single pole switch, Camstat FAL7C 20BT-120-AB, and Camstat L59-7B-A

Hummmmmmmmmm!

OK my way.

One of the 24 volt leads needs to connect to the gas valve, the coil of the fan switch, and the upper limit switch which I think you are calling the gas switch. It opens if the furnace gets too hot shutting off the gas

The other 24 volt lead needs to connect to the thermostat and to the other terminal of the fan switch.

The other thermostat wire connects to the gas valve. Thus, when the thermostat calls for heat, power flows from the transformer to the thermostat and back to the gas valve. If the upper limit switch is closed, it flows through the coil opening the gas valve and back to the transformer through the upper limit switch.

Once the gas has been on for a little, the fan switch closes and power flows from the transformer through it to the coil of the fan control and back to the transformer, turning the fan on.

When the thermostat opens, the gas valve closes, and the fan switch cools of and opens too.

I am not sure how your pilot works. Usually they stay on. Try posting back with more details on it. Maybe one of the better people will see it and help.

letmetellu · Jan 20, 2007, 10:22 PM

I never did understand what you question was. You start by saying that when the switch on your Payne furnace is on the blower runs all the time. That is what it is suppose to do. That switch is a fan switch and a fan switch only to be use in the summer time to circulate the air in the house with you do not need heat or cool, just air movement.

I re-read and still I don't see a question only that statement

Lazarwulf · Jan 21, 2007, 10:43 AM

Thanks for taking a stab at this one. (God I love the internet)

A little clarity. If I toggle the single pole switch on, the blower motor will come on and never shut off, but otherwise everything else seems to work properly. However, if I toggle the single pole switch off, nothing comes on, ever.

The gas switch is really the gas valve (Oops) and it has one wire going to the transformer nut and the pilot light (which is always on).

The transformer actually has 2 leads and 2 "nut poles?" allowing for wire to be connected on the outside using the "nut poles" and the inside using the leads. When you refer to transformer leads which side is that? And what goes on the other side.

Sorry for the confusion. I am a game programmer by trade ;) I work on hotrod cars for a hobby so I have some mechanical abilities. I worked through college as a mechanic.