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Rinnai R65 Help

CraigB Member Posts: 1
Hi all! I have an old Rinnai C85 installed in a basement as a boiler unit. It hadn't had a flush since it went in, being that the installer failed to tell the owner that it had to be maintained. It wasn't running for 5 years until midwinter when I had replaced the flamerod and igniter and bybass servo that was rusted shut. I flushed the lines and started it up and it ran for 2 months. One day it started beeping at the display unit a code 12 and then shut down the unit. I figured something else would go wrong since it hadn't run for so long, so I turned the display off for a few days and when I went to turn the display back on, neither the display nor the unit would turn back on. I opened the panel and checked the fuses and they were fine. I have read numerous posts that indicated a dead unit is 9 out of 10 times a PCB, but before I got a new one I wanted to see if there were any suggestions. Nothing that I can see is fried. The unit is not surged protected. Thanks!


  • Jack
    Jack Member Posts: 1,047
    Without a manometer and dmm you are shooting from the hip on this. As it sat for so long, check and clean the air supply side. It could be crapped up there as well and it is a fairly simple check. I would call the 800 number on the side of the unit, but they will not talk to you without the proper instruments.