On May 25, 10:36 am, "<attitudeiseveryth...@braintrust.com>" Whatever wrote:
> I have a shower stall with a single control knob that controls on\off (pull
> out for cold and push in for off) and hot\cold (left for hot, right for
> cold). The temperature setting on the gas-fired water heater is on the
> "normal" setting. Other faucets in the house seem to produce a lot hotter
> water when they run with only hot turned on. For a year or two now I've had
> to keep the combination hot\cold on\off handle almost all the way towards
> hot to keep the shower hot enough for a decent shower. I finally removed
> the round knob and the escutcheon plate to see what it looked like. There's
> a very small retangular cutout in the tile and the only thing that's visible
> are the two holes that mount the escutcheon plate. The diameter of the
> place where the knob mounts is a little bigger than the diameter of a
> nickel, and it appears to have what looks like the same type of fitting as
> with a garden hose valve when you remove the wheel handle - it looks simply
> an on\off function - I didn't seen anything that looks like other mixing
> valves that I've seen in pictures - nothing that looks like any adjustment
> screws or the like.
>
> Is this a situation where I simple remove and replace what the control knob
> attaches to? When I go looking for replacement parts, what's the proper
> terminology?
>
> If it's going to involve removing tile and all that, I can learn to live
> with it.
>
> Thanks!

A relative in Georgia says that five or six months ago, suddenly one of the showers started only running hot water. Should I call the Georgia state AFL-CIO? How do I find out the name of the last plummer who was there?

It is called a "tempering valve" - what it does is, theoretically, prevent scalds by not allowing the hot water to run alone. Some are thermostatic, most are pressure-based. Those that are thermostatic tend to fail-cold. Those that are pressure-based can fail either way, or altogether. Generally, one must replace the cartridge - that is the internal part that does the mixing - to fix either. In hard-water or high particulate (sediment) situations, failures are quite common and can be very annoying.

Peter Wieck
Melrose Park, PA

On Tuesday, August 29, 2023 at 6:24:12 AM UTC-4, Peter W. wrote:
> It is called a "tempering valve" - what it does is, theoretically, prevent scalds by not allowing the hot water to run alone. Some are thermostatic, most are pressure-based. Those that are thermostatic tend to fail-cold. Those that are pressure-based can fail either way, or altogether. Generally, one must replace the cartridge - that is the internal part that does the mixing - to fix either. In hard-water or high particulate (sediment) situations, failures are quite common and can be very annoying.
>
> Peter Wieck
> Melrose Park, PA

I'm pretty sure this is a 2004 thread risen from the dead.
But anyway, I haven't seen a thermostatic one though they probably exist. All the ones I've seen in a large campus setting has been pressure based but the limit was a mechanical stop that couldn't be adjusted. What we found when we had a lot of complaints, particularly in group shower rooms like at a gym or old dormitory, is that the pressure from hot and cold water supply had to be within pretty tight constraints or these did not work. There was nothing wrong with the valve, but if it got more than maybe 5 pounds pressure on either it got strange results. And that can happen pretty easily with large usage upstream.

https://www.build.com/product/summary/17862?uid=1251587&jmtest=gg-gbav2_1251587&inv2=1&&&&&&source=gg-gba-pla_1251587!c1709211103!a69367398840!dc!ng&gclid=Cj0KCQjw0bunBhD9ARIsAAZl0E2fa2POcWUBaCaI6wZEWhHjaViJi70J6TDiEi2cVFNLvWWaG_zTPLwaAixoEALw_wcB&gclsrc=aw.ds

Peter Wieck
Melrose Park, PA