Pressure Balance or Thermostatic Valve?

15 years ago

We're building in the country, and are buying plumbing fixtures from Restoration Hardware. They offer either thermostatic or pressure-balance valves for the shower.

We are not planning anything extreme for the three showers in the house--good shower head and separate handheld shower for each. We see the handheld as an occasional accessory, or for rinsing soap off the walls.

I have heard there are problems connecting thermostatic valves to instant/tankless water heaters, but we're not yet committed to domestic hot water system. I've also heard that there's more to break on a thermostatic valve.

There may be times of high water usage (three and a half baths plus kitchen), and I know our well is capable of keeping up flow requirements, though have heard there can be occasional fluctuations from the pump kicking on to refill the pressure tank.

Your thoughts and experiences appreciated on which type of valve we should use. One other option is to use the thermostatic valve in the master, but the other two baths get pressure balance types??

Thanks! Mark

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Comments (5)

zl700
15 years ago
You have that reversed, there are sometimes problems connecting pressure balanced valves to tankless, because of pressure drops on the heaters.
I would go thermostatic. These offer the best scald control besides

With regards to a well system, all tankless have some trouble with pressure fluctuations. Well bladder tanks don't even the operating pressures for very long, only offer a differential to allow for pumps to keep from cycling. 20 PSI is the norm for standard well systems so, you will feel that change. Unless of course, you go with a constant pressure well pump system which having had one in the past is well worth the expense, especially when you factor in the energy savings since the pump is variable speed.
wa8b
15 years ago
The other reason you'll like a thermostatic valve is that you won't have to fiddle with it every time you get into the shower. Once you find a temperature that you like, you just leave it set there. Each time you turn on the water, you'll automatically get water at your preferred temperature.

I seldom alter the temperature setting. I just turn on the water a few seconds before I step into the shower (I have a hot water circulation system). I know the shower will be at just the temperature I prefer.
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I am thinking that you simply are reacting negatively to the newly implemented 2.5 gpm restriction. As you point out in your other thread, going from 8 gpm to what you have now is a huge adjustment. Will your plumber (or contractor) tell you if 3/4" pipe was ripped out? Or was it also 1/2"? You are right that either are in the code, but does the valve and shower head combo prevent any difference in what gets to you in the shower, anyhow? Does your apartment building now require 1/2" and that is why you got it? However, if the supply valve is supplying a satisfying pressure at a "warm" setting, where both hot and cold are mixed, I understand your question about why you can't get the same pressure and volume of water when you turn to only hot water. Barnes Custom Builder does not address that in their first answer. It sounds like you are willing to replace your valve if that will get you the shower you want, you just want someone with more understanding of the way these valves work to give you word that it will be worth it. I can understand your reasoning about the valve you have, because the handle controls both volume and temperature, you should have max volume at the highest temperature, yet you are getting less pressure with just hot water being called to the shower. What is going on? Does pressure coming from the hot water tank naturally differ from the pressure of the cold water delivered directly from the city? These are all questions that a plumbing professional with an understanding of the dynamics of this type of apartment building situation needs to address with you.
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goofyny13_aol_com
15 years ago
Just curious -- I'm looking at thermostatic valve/trim set for a master bath. found a company called Hudson Reed, from the UK who seem to price much less expensively than US manufacturers. Have you heard of them? Know anything about them? Their website for the product I'm looking at is: http://usa.hudsonreed.com/product/Hudson_Reed_Kia_Jule_Triple_concealed_thermostatic_chrome_shower_faucet_valve/286/39878.html

Would be interested in your opinions here -- or if you have US company that is comparably priced.
alphonse
15 years ago
Mark G, since you will have a well, pump & pressure tank water delivery system, take a look into cycle stop valves. While not solving pressure fluctuations entirely they make great inroads towards the problem as a side benefit to their main purpose.
I don't sell them nor work for the mfg. but see no problem promoting their use.
j3513
10 years ago
zl700, we are having problems with our tankless water heater during the winter months. We will turn on the hot water in the shower (full hot), wait for it to heat up, and then dial in a comfortable temperature before stepping in. In the middle of the shower, the water heater will suddenly shut off, indicating an error code, and of course the water becomes ice cold. We have found that simultaneously running the hot water on a second faucet, for instance the bathroom sink, prevents this problem. We have PBV's in our showers and are looking to replace them with thermostatics in order to eliminate this problem, but it would be nice to find some published literature that confirms that this is likely to remedy the situation, especially given how invasive a valve replacement can be. Can you tell me where you learned about the possible problems with using PBV's with tankless water heaters?

Pressure Balance or Thermostatic Valve?

Comments (5)

zl700

wa8b

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