No hot water in shower

Mark15

There are 3 showers in my house that only have lukewarm water about 84 degrees. The water will come out at 105 degrees for a couple of seconds before cooling down. It's a symmons temptrol control. All the sinks in the house produce plenty of hot water. The limit stop has been turned up in the showers and I have also replaced the spindles. There is still only lukewarm water. What else could be the problem?

Thanks

djlandkpl

Are both hot and cold supplies for the showers/entire house fully open? The Temprol valves won't work correctly if the water pressure is out of whack.

Mark15

Water pressure is good. When I moved in in December the water pressure was low but it has since been fixed.

djlandkpl

Are any of these tub/showers? Are you able to increase the temperature by turning the handle counterclockwise? It's very strange that all 3 are affected.

Mark15

One is a tub/shower and the other two are stand up showers. The temperature does increase but caps out at a lukewarm temperature, even when it's turned all the way to hot.

djlandkpl

It seems to me as if there's a volume problem. On the tub, if you have it on full hot, is there a noticeable difference in pressure and volume compared to full cold?

It's also possible that cold water is getting mixed into the hot side from another fixture.

djlandkpl

As a double check, what steps did you follow to set the limit screw?

Do you have any single handle cartridge style faucets in the house?

Mark15

Took the knob off and loosened the screw- at least two turns but the water wasn't any warmer when I tested it. The kitchen sink is a single handle faucet- plenty of hot hot water.

djlandkpl

These are from the instructions to set the limit. Not sure if it makes a difference since you moved the screw out not in. Might be worth a try.
To set the limit, open valve to maximum desired temperature and turn
in limit stop screw until it seats.


Try the tub test for pressure/volume and temperature.

To check for crossover, turn off the cold water supply to all of your fixtures and see if the problem stops.

Mark15

Hmm the direction I had said to loosen the screw to increase the hot water but I did try it the other way. Turning it in made the knob turn less and had colder water. I did try loosening it even more but still not hot water. Also, I tried the hot water in the washing machine, which is upstairs on the same floor as 1 stand up shower and the tub/shower, apparently that also does not get hot water for more than a few seconds. The tub has the same temperature and the pressure seems good, to me anyway. I did not try shutting the cold water off yet.

djlandkpl

What was done to fix the water pressure problem?
What type of water heater do you have? Conventional/Tankless?

Were you able to get full hot water out of the tub?

Mark15

A heating guy came and I believe replaced a mixing valve and said the water pressure would be better. He was there for other heating issues (furnace wasn't starting up all the time) so Im not exactly sure what he did for the water pressure - it wasn't terrible before he came anyway. I have a tankless water heater. Water from the tub is the same temperature as the shower.

djlandkpl

Have you ruled out cold water crossing over to the hot side?

I don't know much about tankless but I'm thinking it's not firing at 100%. Have you checked the water heater operation?

Ghostmaker

Do you have a hot water recirculation system installed?

Mark15

I just moved in in December so I'm not sure about the hot water recirculating system. How would I check for that?

It's an old furnace but I was told it was still 84% efficient and if there was hot water in the sinks then it was producing hot water. I have not yet ruled out cold water cross over.