Water gets hot when showerhead paused

[scenthound]

My bathtub has a Moentrol single handle system. I recently installed a new handheld shower head with a "pause" feature (Located on the shower head itself) which limits the full flow to a trickle. When paused, the temperature of the water trickling out of the faucet, as well as the shower head, will start to slowly increase until it is extremely hot. Once the shower head is "unpaused" and the flow has resumed, the temperature will eventually return to normal after ~10 seconds but during this period the water is still very hot. Any idea how I can remedy this behavior? I am concerned about somebody scalding themselves accidentally.

 

[breplum]

First thing to be done is to shut off the water and remove and service the balancing spool by lubricating and cleaning.

How is the operation of the control itself? Does it pull out smoothly? if not, then replace it, bc there may be a part that has deteriorated, though in 45 years I've never seen a bad o-ring inside.

The balancing spool system isn't designed for pausing, but I can imagine some hydraulic principle that will be the cause w/no hope to solve your issue.
Unless you have a tankless WH, in which case, that can happen anytime unless it is a Navien with a mini-tank.

 

[skeezix]

My shower does the same thing. When I close the valve that's just ahead of the shower head so I can soap up, the water that flows out after I open it is pretty hot. It does cool down after 5 to 10 seconds though, and I've learned to live with it (after 25 years)...

 

[Geofd]

Those showers are not meant to have pause buttons unless the shower valve was installed with check valves
What’s happening is the hot and cold water are crossing over/ when you push in the pause button you are essentially connecting the hot and cold pipes tighter
We have a similar situation at work the we have handi cap showers with a separate diverter control
The students use that to shut the water off rather than the mixing valve itself I causes the same situation
Remove or don’t use the pause button/ or just shut off the water when soaking up

 

[skeezix]

It was back in the mid-80s when I read the water meter before and after taking a shower. I saved the reading and the next time I took a shower I did the same thing but I turned the shower head valve off to soap up and wash. (But it still dribbled a little bit). Then I compared the readings and found out that I saved roughly 1/3 to1/2 of the water with the valve off. Been doing that ever since...