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Very high CO levels at exhaust. Looks like burners leaking gas...

MikeThomas Member Posts: 2
Had a home energy audit conducted and the inspector wasn't able to get a CO reading on the exhaust because the level maxed out his meter. I've read that this is typically a sign of a heat exchanger failure but when observing the unit under operation, the flames do not dance around when when the blower turns on. However, it looks like there is an auxiliary flame occurring between the burner tubes. Could this attribute to the high CO levels in the exhaust? Here is a video of the burners running just before the blower and then while blower is running. https://youtu.be/lNeMjo_BktY

The unit is a Carrier Weathermaker SX Model: 58SX080-BC-1 and installed in 1985. Last year had the three-wire pilot replaced and the tech made a comment that this has several "upgrades" and isn't all original. Not sure what that means but, ok.


  • John Mills_5
    John Mills_5 Member Posts: 952
    Plugged secondary, notorious on old Carrier 90s.
    JUGHNE Member Posts: 11,094
    Has the manifold gas pressure been checked?
  • MikeThomas
    MikeThomas Member Posts: 2
    Gas pressure has not yet been checked. Hoping to get opinions on calling for service or quote to replace. The primary and secondary exchangers were replaced about 10yrs ago.
  • lchmb
    lchmb Member Posts: 2,997
    the flame between the burners is normal. As mentioned previous, high co level's are a strong indicator of a plugged secondary HX. Do yourself a favor, dont replace the HX just replace the unit...
  • Firecontrol933
    Firecontrol933 Member Posts: 73
    Bad secondary HX. Time for a new furnace.