Preventive Maintenance
Posted: Wed Sep 26, 2007 1:36 am
I pulled apart my furnace to clean the 21 years of dust accumulation, everything went fine but during the clean and inspect I noticed the middle limit switch was charred in half in fact the wire and lead came off in my hand. My technical skills are on point and I like to think there isn’t too many things I can’t fix, however my knowledge of furnace repair =’s a big fat zero . I really need your help in this area.
My furnace is an Electric Coleman Model 3400A816 with a two wire thermostat.
Looking at the schematic I see the middle limit switch hooked to the middle heating element and than to the sequencer. Visual inspection of the three heating elements (now I’m a furnace noob remember) seams to be ok, no charred parts, no breaks, and I used a soft bristle brush to clear any dust accumulation. Also looking at the right side of the sequencer where the middle heating element is attached I can see a little bit where the insulation looks as if it got a little hot but no signs of failure.
I know I need to replace the limit switch, that’s a given.
Should I replace all 3 limit switches or just the one that is charred?
Should I replace the sequencer as well?
Any thoughts on this would be great. Thanks in advance for your time.
r/JP
My furnace is an Electric Coleman Model 3400A816 with a two wire thermostat.
Looking at the schematic I see the middle limit switch hooked to the middle heating element and than to the sequencer. Visual inspection of the three heating elements (now I’m a furnace noob remember) seams to be ok, no charred parts, no breaks, and I used a soft bristle brush to clear any dust accumulation. Also looking at the right side of the sequencer where the middle heating element is attached I can see a little bit where the insulation looks as if it got a little hot but no signs of failure.
I know I need to replace the limit switch, that’s a given.
Should I replace all 3 limit switches or just the one that is charred?
Should I replace the sequencer as well?
Any thoughts on this would be great. Thanks in advance for your time.
r/JP