Coleman Furnace High Aux. or Spill Limit Switch open


  #1  
Old 01-29-09, 04:04 PM
P
Member
Thread Starter
Join Date: Jan 2009
Location: Michigan
Posts: 1
Upvotes: 0
Received 0 Upvotes on 0 Posts
Question Coleman Furnace High Aux. or Spill Limit Switch open

I have a Coleman high efficiency natural gas furnace in my mobile home. Model# DGAD070168. Also have central air. Blower runs constantly, unless thermostat is at lowest setting, or off. Thermostat fan setting is set to AUTO. NO heat. Furnace has electronic ignitor. Not igniting. Have tried resetting furnace multiple times. Installed new air filters. Don't smell any gas, and hot water heater is working fine. Diagnostic Indicator for "four flashes" reads as High Aux. or Spill Limit Switch open. Is there a way to "close" this switch, or do I need to replace something? It's really cold outside, and inside!
 
  #2  
Old 01-29-09, 05:05 PM
E
Banned. Rule And/Or Policy Violation
Join Date: May 2007
Location: Wisconsin
Posts: 7,826
Upvotes: 0
Received 1 Upvote on 1 Post
On a newer Coleman furnace we had in one of our mobile home rentals, the limit switch was up above the burner compartment on the left. 2 wires going to the limit with a resettable small button between the wires. Look and see.

If that is what it was, then reset the furnace as well, by shutting it off so that it erases the current status of the blower keep running, so it can start fresh.

Then you have to figure out why it is limiting? Is the furnace grill plastered with dust? Did someone put it in a closet that cannot get enough return air into the furnace? Dirty filter(s)? Registers blocked or closed?
 
  #3  
Old 01-29-09, 06:24 PM
xpogi's Avatar
Member
Join Date: Dec 2008
Location: Kansas
Posts: 92
Upvotes: 0
Received 0 Upvotes on 0 Posts
Originally Posted by ecman51`
...the limit switch was up above the burner compartment on the left. 2 wires going to the limit with a resettable small button between the wires...
The manual reset limit switch is on the blower shelf. It normally only opens if the blower fails. There is also an auto-reset limit on the vest panel above the burner assembly. The two limits are wired in series. I have seen a couple defective auto-reset switches that opened and never closed. Best way to check them is with an ohmmeter with power off the furnace. Switches should have continuity across the two terminals. Don't forget to try resetting the upper switch.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: