Rinnai Tankless - strong vibration

[pkgreen546]

Hello,

Amateur plumber here.
I installed a Rinnai tankless water heater a couple months ago and it’s awesome. The only problem that I can figure out is that when we use the shower or washing machine(both pull a lot of hot water), the water heater has a massive, loud, house shaking vibration for a about 10 seconds, then it’s fine.
I tightened the vent tube and that did reduce how loud the vibration is, but that did not solve whatever the root cause is.
Anyone had a similar issue and know what the cause/solution is?
I added two videos; one you can barely hear the vibration and it’s pretty quick, the other is an example of the “house shaking” vibration.
thanks!

-Pete

 

[breplum]

This is what the tech desk at the mfr is all about. We just call and they help guide us.

 

[pkgreen546]

This is what the tech desk at the mfr is all about. We just call and they help guide us.

Hadn’t thought of that. Thank you, I will give them a call!

 

[Twowaxhack]

You might need a digital manometer or they’ll ask you to call back.

 

[Brad.smith3485]

Hello,

Amateur plumber here.
I installed a Rinnai tankless water heater a couple months ago and it’s awesome. The only problem that I can figure out is that when we use the shower or washing machine(both pull a lot of hot water), the water heater has a massive, loud, house shaking vibration for a about 10 seconds, then it’s fine.
I tightened the vent tube and that did reduce how loud the vibration is, but that did not solve whatever the root cause is.
Anyone had a similar issue and know what the cause/solution is?
I added two videos; one you can barely hear the vibration and it’s pretty quick, the other is an example of the “house shaking” vibration.
thanks!

-Pete

Sounds as if exhaust fans are loose or defective.. or "squirrel cage" area is bent and causing rubbing as the fan spins. Best to call tech support though.

 

[breplum]

At some (Navien, for sure), tech desks, they no longer want to waste time with homeowners/DIYs and only will speak with professionals (and manometer owner).
I completely understand and don't blame them for that position.

 

[pkgreen546]

Sounds as if exhaust fans are loose or defective.. or "squirrel cage" area is bent and causing rubbing as the fan spins. Best to call tech support though.

Brad, you were right. The fan/motor assembly was bent. I replaced it today with a new one and I’m good to go.
thanks for the help; you know your stuff.
-Pete

 

[Twowaxhack]

Brad, you were right. The fan/motor assembly was bent. I replaced it today with a new one and I’m good to go.
thanks for the help; you know your stuff.
-Pete

How did you get the part ?

 

[pkgreen546]

How did you get the part ?

I got the part on supplyhouse.com

 

[Twowaxhack]

I got the part on supplyhouse.com

Rinnai didn’t warranty it ?