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Alpha Intec 34C boiler throwing low voltage error

Just had a new kitchen with an induction hob fitted and now boiler throwing a low input voltage error (E37) every 24 hours or so- stops heating water until restarted. Can't replicate the problem turning appliances on and off, and the house is only 2 years old with a 100A board (professionally installed)
Any tips on chasing this down?


  • Jamie Hall
    Jamie Hall Member Posts: 20,447
    The induction hobs take a lot of current. Somewhere -- quite possibly at the entrance itself -- you are drawing enough current to drop the voltage. Your only bet on chasing it down is to have someone actually record that voltage at various points to see where the wiring is inadequate. Your grid supplier may help. May not, too. Some electricians have that capability.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • BobC
    BobC Member Posts: 5,380
    I agree with Jamies comments above.

    DO NOT TRY THIS IF YOUR NOT COMFORTABLE WORKING ON 240V CIRCUITS. If your comfortable working inside the electric panel monitor the voltage on the boiler circuit breaker while someone turns the induction on and off. If that looks ok (no undue dips) then monitor the voltage at the boiler itself while having someone turn the induction on and off.

    One thing to be aware off is any voltage dip may be very brief and not easily detectable with most meters. Do bulbs dim noticeably when turning the induction unit on and off?

    It is possible some things were not tightened down fully so someone has to check that everything is tight from the main input lugs on down. REMEMBER THESE WILL BE LIVE SO DON"T DO IT YOURSELF UNLESS YOU ARE USED TO WORKING ON LIVE CIRCUITS - this sort of work is best left to the pro's.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • chrisp_2000
    chrisp_2000 Member Posts: 2
    Can't replicate turning hobs on and off. Loddeg mains voltage- never dipped below 240V when error appeared. Put a 240V UPS on the supply and restarted. Could shut off supply to UPS and boiler did not error. Repeated a few times with no error. Left boiler for a couple of hours with UPS on and error has reappeared. Could it be a PCB issue?
  • Jamie Hall
    Jamie Hall Member Posts: 20,447
    Could be, indeed. Could also be a bad enough connection from the power to the unit that it drops the voltage at times; those tend to be erratic. Check all the connections for tightness.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England