Limit switch

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Posts: 1
Joined: Tue Nov 01, 2011 11:58 pm

Wed Nov 02, 2011 12:24 am

Hi there,

I have an old Martin Industries vented wall furnace model # GWF35LP, which has a high limit switch of 36TVG0165. From your site I learned the 36T-part refers to size - and I assume the 165 is the cutout temp. The length of this baby is 5", and is mounted on a small bracket near the top of the furnace. No fan, runs on miliampere tstat (when power is out this baby runs!)

Lately though it fails to start; but when limit switch wires shorted it does - every time. So I assume it's the switch, and that's why I'm looking for one ... though no place to be found. Here is the number stream I found on the insulating board (of the switch):
36TVG0165 44739 09628
L350-60F 072192 MEXICO

If I can solder a new switch to the existing arms looks like you have something similar, like your # B13702-54, or even the B1370188. I just don't know how mine is attached (did not look under the insulation), or whether soldering is secure enough. Mine sure looks like your "L300-40F Nordyne limit switch 5" 626495"

Any ideas?

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Posts: 742
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Location: Aberdeen, SD

Thu Nov 17, 2011 12:39 pm


According to the numbers on your switch, your temperature is a L350-60, meaning that it trips open at 350 degrees and resets itself at 290. Our 626495 would work temporarily work in your furnace, but you could have some nu-sense trips as it's set to trip at 300 degrees.
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