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Lennox Pulse won't keep running

MTerry Member Posts: 1
I'm sorry I don't have as much info as I should, but here it goes.  I have a natural gas Lennox Pulse system from 1989 (model number is at home, I'm at work) and it works fine and blows nice warm air when I first turn the thermostat to heat.  The problem is that it only runs for 1 cycle and then shuts off.  If I turn it off then turn it back on, it will run for 1 more cycle.  Doing this I had the house in the 70's yesterday when it was 30 degrees outside so I know the heater itself works.  I also replaced the thermostat since I thought that could be the problem (and I wanted a new one anyway.)  This might also help, last summer the a/c unit in it decided to leak water everywhere and then stopped blowing cold air.  Could this be residual damage or be related to the a/c problem?


  • Slimpickins
    Slimpickins Member Posts: 330
    Lennox Pulses

    You need to replace that furnace asap or call someone who is familiar with Lennox furnaces and have the heat exchanger tested.  That year (82 - 89) had major heat exchanger problems and they had a recall. I believe the heat exchanger had a 20 yr. warranty and most of them have been replaced.  Since you're out of the warranty, start getting bids for a replacement.
  • don_9
    don_9 Member Posts: 395
    Lifetime warranty

    on hx to the original home owner.iif he is and can prove a crack after the hx has been tested then lennox will give him a new furnace to replace it.
  • Tim McElwain
    Tim McElwain Member Posts: 4,580
    Let me just add

    this, make sure you call a certified Lennox service company as they are sometimes skeptical about non Lennox techs condemning their units.

    If the AC coil was above the furnace heat exchanger and was leaking it probably damaged the heat exchanger and may also have affected some of the electronics.

    Do you have Carbon Monoxide detectors i9n your home? If not I would encourage you to get detectors for your families protection.
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