Rinnai RUR98i - 5 years old - Error Code 63

[jsdtx]

When the recirc feature comes on, we are getting error code 63. Started about 6 months ago, once every few days and now it happens every time. We can get about 15 minutes of hot water before it kicks off. System flushed, plumber looked for air pockets, looked for cross overs. We do have hard water and a basic softener before the system. Anyone had a similar situation? Honestly, I am going back to a tank system if I cannot fix it. The cost of tankless has doubled in the last few years and if you cannot get 10 years out of them, they are not worth it.

 

[Twowaxhack]

When’s the last time it was cleaned ?

 

[jsdtx]

It was cleaned twice by plumber in trying to address this code. But over the 5 years, I cleaned it every 18 months. Maybe not enough. Thanks

 

[Twowaxhack]

It was cleaned twice by plumber in trying to address this code. But over the 5 years, I cleaned it every 18 months. Maybe not enough. Thanks

Contact Rinnai support to troubleshoot and have a quality electrical test meter ready to go.

That’s the easiest thing for you to do and it’s the cheapest.

I’m assuming it was cleaned with vinegar per instructions.

 

[jsdtx]

Called a Rinnai recommended plumber. He got support on the line. They first asked him to check screens for debris. They checked to see how the recir loop had been done in the machine. Was it a replumbed recirc or one that you had to do after the fact. Given that it was preplumbed, they determined the machine was not set for that. They changed out a part. Then they had me turn on hot water and they sought to cut off the hot water from the machine and it kept running cold. They determined that the check valve was malfunctioning and needed to be replaced. They think the check valve caused the error code when the cold crossed over into the hot water. They also did not like two things. They want two check valves, one on the recirc loop and one on the water coming into the unit. They also want an expansion tank on the recirc line. My plumber says the RUR 98i does not need two check valves or an expansion tank as he says that is built into the system. Because that costs so little, I think we should do it. NOTE: I am not trained in plumbing so my description is probably unsophisticated. I apologize. Any thoughts? Thanks John

 

[breplum]

Pretty much every mfr recommends two check valves if there is not a recirc loop tap on the WH. Makes for a closed loop system and so obviously an expansion tank. The little style Zilmet exp tanks are fine for smaller homes.