DIY Home Improvement, Remodeling & Repair Forum > Appliances > HVAC > Very old forced air gas furnace keeps running.





Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old 11-16-2011, 07:31 PM  
paul52446m
Senior Member
 
Join Date: Oct 2010
Location: Houghton Lake, Mi.
Posts: 435
Liked 1 Times on 1 Posts

Default Very old forced air gas furnace keeps running.

Quote:
Originally Posted by auntybb View Post
Hi Paul, My camera wouldn't take really-close closeups, so this is the best that I can do. I tried to get all of the angles, but I had no idea what I was looking for. I have one more photo, but the message would only let me send five. I'm curious to know if you can even see what's there. Thanks again. Kathy
Ok first lets id the parts, Pic. 2 is your gas valve. Pic. 3 right top is your fan and limit switch.
In pic. 5 there is a small wire entering the furnace. This wire looks like it's tight against the metal on the top side of the hole. Check that out to make sure you don't have a bare wire touching the metal furnace.
Leave the door off the furnace so you can see the burners. Now when you turn the stat down and its still going, take and tap the side of the gas valve, this could let us know if we have a sticky gas valve.
If it still on then in pic. 2 you have 3 wires on the front of the gas valve,
take a pair of pointed pliers and take the left hand wire off and see if it turns off. if it does then the problem is in the stat or wires going to the stat.
This unit looks pretty rusty, stand in front of the furnace and have someone
turn the furnace on. Get down so you can watch the flame on the burners.
When the blower comes on is there any flame floating around. If there is you need to have the heat ex-changer check because you could be getting
carbon monoxide.
Are there any other bare wires in the furnace?
There is a wire going from on top the gas valve over in front of the fan switch and it keeps going to the right, where does this wire go?
Start checking out these things and get back with me. Paul


__________________
paul52446m is offline  
 
Reply With Quote Quick reply to this message
Old 12-05-2011, 10:52 AM  
auntybb
Junior Member
 
Join Date: Nov 2011
Posts: 8
Default

Hi, Paul, Getting back to you has been delayed by a case of the flu and a death in the family. So life goes.
I followed all of the steps that you gave me, and nothing changed. The furnace seems to burn clean and to snap right on. Removing the wire didn't turn anything off. Nothing is touching the furnace. I guess that some sort of switch or timer must be bad. But you're the expert. Please give me more directions, because so far it's been fun. Thanks. Kathy



__________________
auntybb is offline  
 
Reply With Quote Quick reply to this message
Old 12-05-2011, 03:56 PM  
paul52446m
Senior Member
 
Join Date: Oct 2010
Location: Houghton Lake, Mi.
Posts: 435
Liked 1 Times on 1 Posts

Default Very old forced air gas furnace keeps running.

Quote:
Originally Posted by auntybb View Post
Hi, Paul, Getting back to you has been delayed by a case of the flu and a death in the family. So life goes.
I followed all of the steps that you gave me, and nothing changed. The furnace seems to burn clean and to snap right on. Removing the wire didn't turn anything off. Nothing is touching the furnace. I guess that some sort of switch or timer must be bad. But you're the expert. Please give me more directions, because so far it's been fun. Thanks. Kathy
In your pic. you have a fan switch with 3 or 4 wires going off to the right. Those wires go to another box about 6" sq. There is a lot of wires in that box. take the cover off that box and take some more pic. Paul
__________________
paul52446m is offline  
 
Reply With Quote Quick reply to this message
Old 12-05-2011, 09:39 PM  
slownsteady
Senior Member
 
slownsteady's Avatar
 
Join Date: Jun 2009
Location: Newton, NJ
Posts: 340
Liked 20 Times on 18 Posts
Likes Given: 28

Default

Hi folks, I don't have any answers, but i have a suggestion.

Paul, since it sounds like the problem started when the thermostat was changed,maybe it would be good to start there. It certainly would be simpler to mess with a couple of wires at the stat.

Kathy, I know your friend has hesitated to call in a technician because of the cost, but after burning fuel for a month, it might be less expensive than letting it run.

Just a couple of thoughts...

__________________
slownsteady is offline  
 
Reply With Quote Quick reply to this message
Old 12-06-2011, 08:51 AM  
auntybb
Junior Member
 
Join Date: Nov 2011
Posts: 8
Default

Hi, Paul,
Will do. I'll get back to you.
SBS, the thermostat was changed because the problem had already happened. She turns off the power to the fan to shut off the fan, so the furnace doesn't run constantly.

__________________
auntybb is offline  
 
Reply With Quote Quick reply to this message
Old 12-06-2011, 12:22 PM  
tflatebo
Junior Member
 
Join Date: Dec 2011
Location: Minneapolis, Minnesota
Posts: 1
Default Check your filter

Make sure your filter isn't clogged. The easiest way to do this is to remove it.

__________________
tflatebo is offline  
 
Reply With Quote Quick reply to this message
Old 12-06-2011, 02:54 PM  
auntybb
Junior Member
 
Join Date: Nov 2011
Posts: 8
Default

Hi, Paul, Here are the photos, although I wasn't able to remove the cover of the case because there is another square thing with wires on top of it. If these don't give you enough information I'll send more. Thanks again.













__________________
auntybb is offline  
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter DIY Home Repair Forum Replies Last Post
Trouble with Coleman 2880C766 gas forced air furnace rsiders HVAC 3 10-24-2013 09:12 AM
Gas Furnace Blower/Fan Occasionally Keeps Running Dr_Zoidberg57 HVAC 9 01-24-2013 09:37 PM
Forced Air furnace: air has unpleasant smell aglie HVAC 5 10-24-2010 06:27 PM
Oil furnace trouble after running dry basscop5000 HVAC 2 06-30-2010 02:41 PM
forced hot air furnace upgrade mannvel HVAC 0 08-13-2007 09:47 PM