RV Shower Hot (or cold) water blast

It's simple physics. Heat rises. If you have a column of water the hottest water will rise to the top. The same principle at work in your water heater. Ever wonder why the cold goes in the bottom and the hot comes out the top? And before somebody say the cold goes into the top of their heater, if it does there is a pipe internally going to the bottom.
A check valve is not going to help. Letting it trickle will help some. Pointing it at the wall when you turn it on will work every time you remember to do it.

If your hot water tank has only ONE valve for the bypass, that could be part of the problem. the other end has a one way check valve that is not a linear flow with pressure. Result is that water temp changes based on flow rate. Our dealer says they have lots of issues and recomend switching to a bypass that has two valves like the old kind and pulling the one way check valve on the tank. Did that and the problem virtually disappeared on our trailer

Old-Biscuit wrote:
Turn shower head against shower wall when turning back on

Thanks, the problem is I probably will have to get blasted with cold water once every shower for a couple of years before I remember. Could be interesting for guests. Do I tell them? Once I find out their political persuasion I can decide whether to tell them or not.

Dutch_12078 wrote:
I installed check valves on our shower feed lines to eliminate the backflow issues that cause the hot/cold blast when the shower head shutoff is used.

Thanks. Where did you install check valves? I assume it doesn't matter where you install them?

Old-Biscuit wrote:
Turn shower head against shower wall when turning back on

This ^^^^^^^^^^^^^^^.

Do not turn water all the way off at the shower head. Let it trickle just a little. Temps stays consistent. You can buy replacement shower heads that do that.

This was discussed several years ago.
On our last couple of mh I go to Tractor Supply and get nylon pipe to garden hose fittings and a garden hose valve and install it at the shower head.

Cheap and easy, put one hand over it when turning it back on.

Turn shower head against shower wall when turning back on

Installed A Thermostatic Shower Mixer Valve

This WILL fix the problem, and a few others as well. Like, fiddling with the knobs adjusting the temperature, and wasting water because you have to point it towards the wall.

Admittedly, it’s the most expensive way to resolve the issue, and at least in my case wasn’t an easy install. But, if your freshwater tank is on the small side like mine is, and you spend more time camping with no hookups than in a FHU parking lot, this is well worth the cost and effort.

:):)