Why doesn’t RV’s bathroom faucet have hot water while others do?

Dear Dave,
I have hot water everywhere except in the bathroom sink. Replaced the faucet valve; good water pressure but no hot water. Water heater is working fine. —David, 2011 Itasca Reyo 25T

Dear David,
Have I mentioned lately that I LOVE Winnebago questions? [The Itasca Reyo was built by Winnebago Industries.] According to the plumbing schematic on the Winnebago site, the cold water line comes into the water heater from the filter and “T’s” before the water heater bypass valve, with one cold line going to the bathroom sink. Hot lines come off the water heater and one also goes directly to the bathroom sink, so this should be fairly straightforward.

I have a couple of questions. First, has this just started or has it been this way for a long time? If it has been since you have had the coach, it could be a plumbing mistake with the hot water line capped or not ran at all. But let’s assume it just started.

According to the 3D diagram, your bathroom sink faucet is a single handle version PN 165378-02-CHT, which means it has a sub directory (CHT).

Next question: When you direct the single handle to the hot side, do you get any water flow? A single-handle faucet should divert the valve opening to just cold when moved all the way to the right, and just hot all the way to the left. It can mix in-between; however, it should not have cold water flowing when in the hot position.

I would recommend shutting off the water supply underneath, if there is one. Or make sure the city water is not connected and the onboard pump is off. Then remove the faucet and test the hot and cold line.

Get a cap plug from a home improvement store and cap off the cold water line. Turn on the water pump and see if there is flow from the hot side. If there is flow, it might take a while for the water in the line to flow through the pipe and hot water to get there—so make sure you have a large bucket.

If it does not flow, there is an obstruction somewhere upstream. It could be directly at the connection itself. Use a small wire brush or small screwdriver to check for any sediment clogged in the line. If there is water flow and it does get hot eventually, the faucet is bad and you should just replace the entire faucet.

Taking these steps should help isolate the area of the blockage.

DAVE HAS ANSWERED MORE THAN 1,000 readers’ maintenance and repair questions. Read a directory here. There is so much to learn!

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Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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