Noise When Hot Water Turned On

[Dlvgolf]

We’ve been living in RV FT since Nov 2019. Yesterday out of the blue, when the hot water is turned on, there’s a whining sound that seems to be coming from the hot water heater. It only makes the noise when the hot water is turned on. No noise when it’s just cold water. It happens no matter which faucet you turn on, bath room, kitchen, outside. I thought maybe air in the lines, so I drained the hot water heater. No change. Any ideas, thoughts suggestions?
Thanks, Dave

[Bones2003]

This is a common complaint and is caused by the check valves on the hot water heater. Winnebago generally uses one check valve on the cold water inlet to the water heater and another check valve on the outlet. There are lots of threads on this forum about these check valves so I recommend a search for "water heater check valves". That will give you information about replacing them, removing them, modifying them, and/or changing them. Lots of people have lots of different (and passionate) advice about what to do. You will have to read the threads and decide what to do. Generally they are easy to remove or replace if you are handy and, this is the big if...if you can get access to them. Sometimes they are crammed into some very tight spaces.

Good luck!

[Dlvgolf]

Thanks. I’ll start searching

[Dlvgolf]

Originally Posted by Bones2003

This is a common complaint and is caused by the check valves on the hot water heater. Winnebago generally uses one check valve on the cold water inlet to the water heater and another check valve on the outlet. There are lots of threads on this forum about these check valves so I recommend a search for "water heater check valves". That will give you information about replacing them, removing them, modifying them, and/or changing them. Lots of people have lots of different (and passionate) advice about what to do. You will have to read the threads and decide what to do. Generally they are easy to remove or replace if you are handy and, this is the big if...if you can get access to them. Sometimes they are crammed into some very tight spaces.

Good luck!

Found them. Thanks.

[Blastvalve]

+1, sounds like a check valve. Our Sunova had the same issue, we used to say the RV “sang” to us. Not a hard swap, but can be a pain to get to. The Sunova had 2, one on the cold water inlet, and one at the hot water out. I suggest changing both to ensure the noise goes away.