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Boiler exhaust & intake switched: how bad is it?

ChrisG Member Posts: 3
I'm a homeowner who is having trouble with my Peerless gas boiler (PI-80), in service without problems for about 5 years until a couple of months ago.  I hired someone to take a look and the verdict is that I need a new combustion blower.  After looking at the installation I see that the exhaust and intake are switched.  The installation was supposed to use a T fitting (3" PVC) for the intake, extending about 6" from the outside of the house, and a straight PVC pipe extending at least 12" further out from the intake for the exhaust.  Those two pipes are installed correctly but he hooked the straight pipe to the boiler intake and the pipe with the T to the boiler exhaust.

It doesn't seem like this should matter much to someone who otherwise has no clue, but how big of a screwup is this?  How likely  is it that this installation is contributing to exhaust gases getting into my intake?  And if so, how likely would it contribute to my combustion blower breaking?


  • JStar
    JStar Member Posts: 2,752

    Could be a problem. Maybe not. Do you have pictures of the venting on the outside? How long is each run, and how many turns?
  • kcopp
    kcopp Member Posts: 3,815
    The Pinnacle is....

    the same boiler as a HTP Munchkin. They have had blower issues w/ that boiler for many years. That being said the venting should be modified to spec.
  • Zman
    Zman Member Posts: 6,959

    I think your suspicions are valid,I have seen cross contamination cause overheating of the venturi. It is reasonable to think it could have led to the demise of the fan.

    I would suggest you have the venting corrected, then have the boiler intake carefully inspect and a combustion test done.

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • ChrisG
    ChrisG Member Posts: 3

    Here is a pic of the pipes.  Left: intake, right: exhaust.  They are 16" apart (on center), and the left pipe extends 13" beyond the right pipe.  The intake has two 90 deg bends, one 45 deg bend, and 12' of straight runs.  The exhaust has four 90 deg bends, one 45 deg bend, and 12' of straight runs.

    I am getting the dreaded F14 fault code discussed in this thread:

    I've cleaned the heat exchanger with CLR and a brass brush.

    Any opinions on how much the switched intake/exhaust contributed to the blower breaking down are welcome.
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