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Heatmaker II cycling

JeffZhangJeffZhang Posts: 3Member
Hi I have a Heatmaker II furnace. It heats the hot water (for household use) and the heating gylcol fine, but cycles itself too frequently - every 10 minutes or so I hear that it stops making the normal working noise and then immediately restarts it.
What could be the problem?


  • ZmanZman Posts: 4,881Member
    Does it show an error code? There are a variety of things it could be. You probably need to have a pro take a look.
    BTW. The heatmakers are not known for longevity. I would plan an upgrade sooner than later.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • JeffZhangJeffZhang Posts: 3Member
    No error code. Other than that it cycles, things seem to work fine. Yes probably need to start looking for a replacement. The cycling itself will put on some stress on the system I suppose.
  • kcoppkcopp Posts: 3,324Member
    Heatmakers were a pretty neat set up when introduced in the mid 1980's
    Mid about 85-86% efficient. Did heat and hot water in a neat package. Hot water output was always pretty darn good. The short cycling issue happens w/ them if a sensor is failing or a relay is bad. Parts are around to replace but are getting harder to find. There are still a fair amount out there but they are starting to dwindle due to the storage tanks leaking or the burner assembly failing. The natural gas versions tended to last longer than the LP gas versions.
  • ZmanZman Posts: 4,881Member
    Heatmaker was bought by Laars and rebranded as "Endurance"
    I know some of the parts cross over.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • aceboileraceboiler Posts: 14Member
    I would have to see a picture of the boiler to be certain of the unit?.
    I had the PVC pipe break inside the storage tank once.
    This goes from the coil into the bottom of the tank and acts like the dip tube of a water heater pulling cooler water off of the bottom and injecting the hot water into the top. If it is broken then you will recirculate hot water off of the top. They short cycle when this happens.
    You would have to check your operator with a multi meter and a temperature clamp. Might just be a control issue.....flow issue.....
    anticipator issue, ice in the vent issue.
  • JeffZhangJeffZhang Posts: 3Member
    Thanks for all the comments and suggestions. I'll take a picture next time I am there.
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