Fluctuating water temps

[cmarkj]

In our shower, hot water flows hot and cold water flows cold. When taking a shower, at normal flow, the temp stays constant. When we push the button to a trickle (oxygenics head) the water temp fluctuates hot/cold/hot/cold. It never happened before until our first trip out a few weeks ago.
The water heater bypass is set to the correct position, both of the outside hose spray connections are capped.
When the kitchen or bathroom sink is running, when the pump strokes, the water gets a a bit hotter just on the stroke then goes back to the set temp.
Does anyone have any ideas?
Thanks

[ktmrfs]

many hot water bypass systems only have 1 quarter turn valve along with a one way check valve on the other port. The one way check valve tends to have a very non linear restriction vs. water flow and pressure. So.... as you turn down the flow on the shower head, the restriction on the one way check valve goes way up and you get an imbalance in hot water flow, much less than expected.

Solution, toss the check valve and install a bypass system with two quarter turn valve. Problem solved.

And if you want to really improve your shower control, install this

shower valve



and then keep the oxygenetics head, but no use the valve to control flow and get constant temperature.

[ralph_day]

When doing a submarine shower (wet, cut water, soap, run water, rinse) I point the shower head away from me. For some reason it will get what feels like straight hot blasting you when you push the slider over for flow again. Only took once to realize that, and you can't get far away from the blast in a tiny trailer shower/tub stall 🙂

[GrandpaKip]

We’ve had 2 Oxygenics shower heads and both did that. Sometimes the trickle is hot, sometimes it’s warm and sometimes it’s cold. But when the button is pushed back in, the temp is the same as before shutting off.

[Bobbo]

On my second RV, and that has always been my experience. A total of 15 years, so far.

[Grit_dog]

Normal, IMO for low flow out of a camper water pump. Either the cold or hot takes a split second longer to reach the faucet than the other, when the pump strokes.