Hot water everywhere but showers

[Brad P]

So recently I have been having this problem:

The two showers (both upstairs, and about 15 feet from each other) can only get lukewarm water. Meanwhile, all the sinks get scalding hot water.

* We have brand new Rheem 50 gallon gas water heater.
* House was built in late 60's

I've tried so far:

1) Heater was set by installer at 130. I raised it to around 135 with no luck. I read that it might be too hot and triggering anti scald device, so I lowered it to 120. Water got a little colder in shower.

2) I took shower head off the one shower and let water shoot straight through pipe, still luke warm


So we know it can't be a shower component, as it would be a huge coincidence that both showers stopped working at same time.

I don't know a lot about plumbing, but I've read it could likely be the mixing valve? So my question is- is there one mixing valve for each shower? There is an access panel for the one shower, but I don't seem to have access to the bedroom shower pipes. The one I have access to looks like this:

(wont let me post a picture since I am new so let me try to figure a way around it)


I am not the handiest person, but I can follow instructions and figure some things out. So can someone at least point me in the right direction?

[akaothermick]

If these are single control shower valves, one knob in the middle. The mixing valve which is the cartridge in the valve could need to be replaced, saying this both going at the same time is strange but not impossible, the cartridges are removed from inside the shower, the front. Most brands are available in the big box stores, of course the water to the showers has to be turned off for this operation. You will need to know the manufacturer and model to obtain replacement cartridges

[Brad P]

Yes they are both single valve. The one shower has a tub with single valve control and flip the switch to change to shower from tub. The other one is shower only.

I wonder if they recent water replacement sent a bunch of debris and clogged the valves?

[akaothermick]

The water to the tub, is it lukewarm too?, you have a good point that possibly dirt and sediment could be impedeing the flow, this could happen on some single control valves, whereas you need to remove the cartridge and check the inlets on the cartridge for dirt, that would be the next move.