Thermostatic Valve Help

[BTAN]

I just had my old shower ripped out and redone. The shower is the same configuration as the prior shower -showerhead, four body sprays on opposite wall, and a handheld shower to the side. I have a Kohler thermostatic valve with three on/off levers above it-one lever for main shower head, one lever for two body sprays, one lever for the other two body sprays-and have one additional on/off lever for the handheld. We changed the piping to Pex all through the shower. We have a tankless water heater.

My main problem is that the water pressure in the main showerhead is not sufficient, nowhere what it used to be and is far less than it is on the body sprays or handheld now. I'm about to contact the contractor but think he will blame the showerhead (Jaclo). I would appreciate any thoughts on what could be wrong and anything we can do to further diagnose the problem.

Other symptons are-When we turn on the showerhead it is the same low water pressure no matter how far the lever is open. The water pressure will fluctuate slightly for no apparant reason and will also fluctuate slightly as the thermostatic valve is turned to adjust the temperature. The thermostatic valve can be rotated 360 degrees but feels like it's running over stops at some points. Turning on or off the body sprays or handheld has some effect on the showerhead water pressure -increases slightly. We're not sure the pressure is where it should be on the body sprays on handheld but definitely more than the showerhead. Also, going from four body sprays to two body sprays noticeably increases pressure on the two that remain on. If that pressure-what is in the two body sprays now-were the same in the showerhead it would be good. Thank you for your input.

 

[Tuttles Revenge]

This is all typical complaints about shower systems.

You need to know your static water pressure at the house.

Which thermostatic shower valve was installed? Its either the 2975-KS-NA 17gpm at 45psi or the 2972-KS-NA 10gpm at 45psi.

Rain showers are notorious for underwelming performance. Which Jaclo shower head is it? How many GPM is it rated?

Your body sprays.. same thing. How many GPM are each of them rated for?

For the overall performance. Think of a garden hose.. open up the faucet and see how far the water sprays.. not very far. Thats analogous to a rain head. Now cover over the exit with your thumb. Less water is coming out, but at increased pressure. Thats like a flow restricted showerhead.

 

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[BTAN]

Thank you for your response. The thermostatic valve is 2975-KS-NA 3/4 THRD. The volume control for the showerhead is K-2974-K-NA 1/2 - 10 GPM flow rate at 45psi. The JACLO is B728-PCH -2.5 GPM.

At this point I don't know what can be done about the water pressure and the pressure issues might be due to the thermostatic valve and volume controls not matching 3/4 and 1/2. I also think the thermostatic valve was installed incorrectly because when lever is rotated slowly I can feel the lever moving over stops and the pressure fluctuates when turning the lever. I'm hoping to have the thermostatic valve reinstalled. I am also wondering if it is possible and if it is a good idea to size down the thermostatic valve since the volume controls are smaller.

I did have a plumber come out and his solution was to remove the restrictor from the showerhead.

 

[Tuttles Revenge]

The thermostatic valve is 2975-KS-NA 3/4 THRD

OK.. that is good. Highest volume thermostatic Kohler makes.
Either of the volume controls would be good enough to run a rain head and should support up to Three 2.5gpm body sprays since even the 1/2" version delivers 10gpm at 45psi.

So maybe you need to check your static water pressure to see if you're at or below that 45psi.. Less psi will deliver less GPM.

On one project we switched body sprays from 2.5gpm to 1(ish) each in order to get more sprays per zone. We had 14gpm delivery from the mixing valve and the HO wanted every shower outlet to be able to run all at the same time.

*edited* had mistakenly thought your volume control was another thermostatic. Kohler numbers were similar.

 

[John Gayewski]

Have you measured to see how each function is performing? It'll be easier to get someone out there to fix something they know isn't working correctly rather than guessing on your part. Just measure the output on each vs what the manufacturer says it should be.