Rinnai fan

[Tbh]

I just had a brand new Rinnai RX199in
Installed two weeks ago and when I use hot water the heater naturally comes on. BUT after using hot water the fan seems to run for a very long time. Note that I have had two Rinnai Tankless in my other home and this never occurred. The fan runs a very long time even if I only call for a small amount of water.
The install tech said this is normal. But I’m not thinking so. Help !!

 

[Phil B]

Some fan run-on after the hot water stops may be part of the unit’s shutdown cycle, but the length of time matters. Since the RX199iN was installed only two weeks ago, I’d time how long the fan continues running after a short hot-water draw and after a longer one.

If it is running for an unusually long period every time, I’d have the installer recheck the setup rather than assuming it is normal. Venting, air intake, condensate drainage, installation settings, and any stored diagnostic codes would be worth checking.

Since this is a new installation, the installer should be able to confirm the expected operation for this specific RX199iN and compare it with Rinnai’s installation requirements.