coldguy
Jan 8, 2011, 09:28 PM
Older Janitrol forced air furnace (1950's), my house is from the 1930's with original wiring in many places... it's sort of scary looking in places.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/Overveiw.jpg
The Blower engine seems to be one speed only (only 2 wires coming out... no grounding line) and is hot to touch and will cut in once in a while but will not turn the blower before cutting out. I have oiled the 2 oil holes on the motor once ever few months. The blower fan is inaccessible and not been cleaned in at least 10 years. Cleaning it tomorrow even though I need to disconnect the cold air return to do it.
I read that the blower may need cleaning or the capacitor needs testing replacing but I can not locate a capacitor on this unit. So far I have done nothing but learn.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/WhiteRoger.jpg
Tracing the electrical into the unit I come to a box marked "White Roger Elec". The W/R box has a second box attached to it. The secondary box has one lead to the thermostat the other to the gas regulator, the gas reg then leads to the Thermostat with one other lead to the pilot ignition. The thermostat leads split in two one to the thermostat the other... shrug.
The W/R box Has Three leads out the bottom. Two goes to the Fan limit Controller (one per side) the third continues and splits between a honeywell box and the blower motor.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/fanlimit.jpg
The W/R box leads to the fan limit controller, an older model with 2 dials (actually two separate boxes), the first ranges from 70-144 and the second 100 - 240, each box has 2 posts on the front. The first box has a line in (black) from the W/R box on the first post and a short lead (red)from the first box to the second box on its second post. The second box has a line in (red) from the W/R on the first post and two lines (black) out on the second post. The second post leads to a small box marked "honeywell" which has two more leads on it but the leads are cut off, could this be the capacitor? Why would the leads be cut?
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/Honeywell.jpg
The other thing that has me scratching my head is the second set of wires coming from the W/R and the Gas regulator. I was thinking maybe a exhaust fan in the attic, does it make sense to have it linked to the thermostat wiring? Maybe at one time they had two thermostats in series (which make no sense to me).
This system seems to not have a ground? Maybe it relies on the gas line to be the ground?
How do you set a dual dial Fan limit device?
For the interim I have a box fan pushing the heat through the system.
I am wondering what the best plan of attack is here.
Hand Drawn Wiring schematic
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/furnacewiring.jpg
**** Cleaned the squirrel cage... no go.
Thinking that the Honeywell is a cap or I don't have one... I found a few posts about old furnaces that had no cap and needed it installed.
Next step is changing the motor, figuring out if I have a capacitor and installing it if needed... off to the store, maybe the store guy could tell me if the HW is a cap.
**** got a new engine, the parts guys assures me I don't need a capacitor with this engine. Everything looks good but the amps are 6.4 on this one... last one was 5.3... again I am assured that is fine. Get home start working to find out shortly the fly wheel does not fit the shaft on the new motor... sigh. Back to the store.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/Overveiw.jpg
The Blower engine seems to be one speed only (only 2 wires coming out... no grounding line) and is hot to touch and will cut in once in a while but will not turn the blower before cutting out. I have oiled the 2 oil holes on the motor once ever few months. The blower fan is inaccessible and not been cleaned in at least 10 years. Cleaning it tomorrow even though I need to disconnect the cold air return to do it.
I read that the blower may need cleaning or the capacitor needs testing replacing but I can not locate a capacitor on this unit. So far I have done nothing but learn.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/WhiteRoger.jpg
Tracing the electrical into the unit I come to a box marked "White Roger Elec". The W/R box has a second box attached to it. The secondary box has one lead to the thermostat the other to the gas regulator, the gas reg then leads to the Thermostat with one other lead to the pilot ignition. The thermostat leads split in two one to the thermostat the other... shrug.
The W/R box Has Three leads out the bottom. Two goes to the Fan limit Controller (one per side) the third continues and splits between a honeywell box and the blower motor.
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/fanlimit.jpg
The W/R box leads to the fan limit controller, an older model with 2 dials (actually two separate boxes), the first ranges from 70-144 and the second 100 - 240, each box has 2 posts on the front. The first box has a line in (black) from the W/R box on the first post and a short lead (red)from the first box to the second box on its second post. The second box has a line in (red) from the W/R on the first post and two lines (black) out on the second post. The second post leads to a small box marked "honeywell" which has two more leads on it but the leads are cut off, could this be the capacitor? Why would the leads be cut?
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/Honeywell.jpg
The other thing that has me scratching my head is the second set of wires coming from the W/R and the Gas regulator. I was thinking maybe a exhaust fan in the attic, does it make sense to have it linked to the thermostat wiring? Maybe at one time they had two thermostats in series (which make no sense to me).
This system seems to not have a ground? Maybe it relies on the gas line to be the ground?
How do you set a dual dial Fan limit device?
For the interim I have a box fan pushing the heat through the system.
I am wondering what the best plan of attack is here.
Hand Drawn Wiring schematic
http://i270.photobucket.com/albums/jj100/GJellyBean/Furnace/furnacewiring.jpg
**** Cleaned the squirrel cage... no go.
Thinking that the Honeywell is a cap or I don't have one... I found a few posts about old furnaces that had no cap and needed it installed.
Next step is changing the motor, figuring out if I have a capacitor and installing it if needed... off to the store, maybe the store guy could tell me if the HW is a cap.
**** got a new engine, the parts guys assures me I don't need a capacitor with this engine. Everything looks good but the amps are 6.4 on this one... last one was 5.3... again I am assured that is fine. Get home start working to find out shortly the fly wheel does not fit the shaft on the new motor... sigh. Back to the store.