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Triangle Tube Soft Lock Out!

thetyro Member Posts: 3
Been receiving the B26 error on my Triangle Tube. PSI is reading around 12-15. Same thing happened 6-8 weeks ago but it went away (I believe after I switched over the pressure relief valve, but I'm not sure). It has been happening again today. I've read about bleeding the radiators but I'm unsure what that entails or whether that's even necessary. I've included pictures below and if anyone has ideas on simple things I may be able to check I'd really appreciate it. Oh yeah, the Grundos Alpha circulator is not flashing any info and so may not be operating for whatever reason-- unsure if that matters.. see pics below. Thanks!


  • Zman
    Zman Member Posts: 7,496
    The boiler thinks it is seeing low pressure.

    There are only a few possibilities:
    You have an inaccurate gage and the pressure is low.
    The pressure fluctuates due to a bad expansion tank or piping issue.
    The pressure sensor on the boiler is bad.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • thetyro
    thetyro Member Posts: 3
    Thanks. Should I just call my HVAC guy in for this one? Last time it resolved itself so I was hoping it might again or that there may be something I could do...
  • JohnNY
    JohnNY Member Posts: 3,226
    Can you add pressure yourself? Get the gauge to read 15-18 PSI when the boiler is cold and see if that doesn't put it to bed.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
  • thetyro
    thetyro Member Posts: 3
    I've tried by switching the pressure relief valve, bring it up to the high teens, but that isn't working.
  • Call your HVAC guy and watch what he does.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • DZoro
    DZoro Member Posts: 1,048
    Have seen some pressure sensors go bad. Let your tech know everything you have tried.
  • ednelson
    ednelson Member Posts: 10
    hello I am a Tech support rep from Triangle Tube my name is Ed Nelson
    The B26 means either the pressure is below 10 PSI which is not the case the other option is something in the system has clogged the Low Water Cut Off in the boiler
    the part number for that is PGRKIT20
    if you have any further questions you can call me in the office Monday through Friday 8 AM till 4:30 PM at 856 228 8881 ext. 155
    thank you
    Erin Holohan HaskellZmanSTEVEusaPA