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Rinnai r53 control display out

jaybra Member Posts: 3
Just bought a house and the rinnai r53 is not coming on. No control display no hot water.no ignition... nothing.
I have power coming in and the fuses are good. Surge protector is good and transformer is good. But nothing seems to be coming out of the board.
Are there other things I should check before buying a new confuser? And if not, the. Where is a good place to get new boards?


    HVACNUT Member Posts: 5,253
    Grounding is very important. Check that first.
    There should be between 90 and 100 VAC (not just "power") on the secondary side of the transformer. At the F2 connector. Between 108 and 130 VAC primary.
    Check incoming voltage. Hot to neutral. Hot to ground. Neutral to ground. If all is good and theres between 90 and 100 VAC at F2, then it's a bad board. And possibly something else that caused the board to fail.
  • rick in Alaska
    rick in Alaska Member Posts: 1,429
    This may sound silly, but I am assuming you pushed the on button on the controller? If you did, then it might also be the control, rather than the main control board. Never had that problem, so not sure how to check it.
  • jaybra
    jaybra Member Posts: 3
    Will double check ground. And yes transformer was showing 101 vac on output side, so I assume that's within operating range.
    And yes did press the on button on controller, also held it for ten seconds, and in sequence with every other bottom on there....nothing. plus it has no power going to it. So if it's broken I have no way of knowing until I get power to it.
    And upon inspection of the power control board the silicone is burnt along with the back of the board. Don't want to assume that's it. And if I change the board and something else is causing it then I'm going to fry my next board. So I guess next step is checking resistance on every component?.....that sucks
    You think they would have more safety's in place to keep from the most complicated component going out.
  • chuxrox
    chuxrox Member Posts: 1
    I had a water event damage this same unit. I ordered and replaced the transformer first thinking that was the culprit and it fried. Then upon closer inspection and following the voltage i noticed the pcb board has some spots burnt out under the wax. The old transformer secondary voltage is reading 105v. Is that in range or too high?