Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Acidic condensate + CO test fails = cracked heat exchanger?

Options
2»

Comments

  • mattmia2
    mattmia2 Member Posts: 9,678
    Options
    A bad hx in a boiler would lead to water leaking out.. on a forced air furnace a cracked hx can lead to draft issues because the blower can force air in to the combustion path through the crack. in a boiler the water pressure will make water leak out of any cracks.

    your issue has to do with the boiler being plugged, the chimney not being designed right or plugged, not enough combustion air so the combination of appliances pulls the interior of the house in to partial vacuum, or the burner not being adjusted right or plugged.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,868
    Options
    Just a thought... does this boiler come with a slow acting gas valve? if so... was it ever replaced? Think about it!

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    JUGHNE
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,868
    Options
    (With a fast acting gas control valve) That might be part

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    JUGHNE
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,868
    Options
    of the problem. Also even if it did not come with a slow acting valve... you might think about changing out the fast acting valve with a slow acting valve.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • mattmia2
    mattmia2 Member Posts: 9,678
    Options
    Or, can the mechanism that makes it slow acting fail?
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,868
    Options
    Just looked at a Rapak parts list for a similar boiler -0135B Yours is a -0135R (Not sure if there is a difference).

    There are several valves available for Nat and LP. Some are fast acting (On/Off) and some are slow acting or 2 stage.

    Have you always had this issue? If NO... When did it start? What changed just before it started? Service, maintenance, or repair just before the problem? Wrong Part or wrong repair?
    Have you had any renovations that may have created a confined space or a negative pressure zone in the boiler area... new clothes dryer with more powerful exhaust fan... new kitchen or bath exhaust fan... have the trees around the vent pipe grown to a point where there is a down draft... or did a neighbor construct a new building 3 stories higher than the vent termination...

    (This may sound outrageous, but that happened the a customer of mine, Someone built a 4 story condo on the property line. His chimney was also near the property line, When the wind came from the north the oil burner coupling melted from the down draft after shutdown.)

    Point being. What Changed between when it worked fine and now? Think out of the box !.!.!

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • HeloDog
    HeloDog Member Posts: 34
    Options
    Well, I’ve decided to stop trying to fix the boiler and just replace it.

    Why? Well one of the members here provided a name of somebody in my neck of the woods who is knowledgable about boilers and might be able to help or point me to somebody who can help. So I called them and talked to them yesterday. Not too surprising, they were quite knowledgable about boilers. And what they said made a strong impression. In a nutshell they said, Yes, somebody could troubleshoot it and probably figure it out - but a gas boiler that starts up with an explosion and shoots fire out the side is somewhat dangerous. And propane just makes it worse. So if you go down the troubleshooting route, then the person doing the troubleshooting needs to be very knowledgable about boilers. As in, they should be able to take them apart and rebuild them, kind of knowledgable. Otherwise, they could make it worse and then really bad things will happen. If you lived near a major city, then finding somebody like that probably wouldn’t be a problem. But here in rural New Mexico where we live, most technicians only know how to install and make minor adjustments to boilers. This problem will be beyond most of them. Unless you know somebody who’s seriously good, the safe choice is move on.

    I’m still getting my head around the fact that northern, rural New Mexico is not like the DFW metroplex where I lived until I retiring recently. THERE I had access to high quality contractors that had to survive in a highly competitive environment. HERE, not so much. On the plus side, it’s quiet, peaceful and rush hour consist of two cars meeting at an intersection at the same time. Every place has its ups and downs, right?

    Thanks again to everybody that provided feedback, suggestions, etc. It’s been very helpful. HeatingHelp is awesome!

    By the way, you’ll see another post from me shortly asking how to tweak my heat load calculation (SlantFin calculator) to account for an Adobe brick house.



    EdTheHeaterMan: Thanks for taking the time to read this discussion and posting your question. Doesn’t matter now, but to answer your question. We moved into the house 2 year ago and have made no changes to it. The problem showed itself the first year. Pretty sure it’s gotten worse. No nearby neighbors or construction. We had techs out to do annual inspection and maintenance on it each winter. The only part they’ve changed was the thermocouple last December.

    FYI: The parts list shows the gas valve as 004825F and I’ve attached a picture of the label on the back of the valve.


Categories