Plumbers: Inline pressure balance valves?? Questions?

LD1 · Dec 8, 2016

I grew up in an old farm house and was used to the occasional increase in temp when someone flushed a toilet. Just thought thats the way things were, and anytime someone was in the shower, you didnt run water period.

When I got a house of my own, it was more modern. Never new what anti-scald or pressure balance fixtures were. Until I owned my house. Boy was it nice. Didnt have to worry about wife doing a load of dishes or laundry, or one of the kids flushing a toilet.

Fast foward to now, I live in a 1987 house that doesnt have this luxury. And want to correct that.

The way the house is laid out, I "could" access the back side of one of the showers via removing drywall in one of the closets. But really dont want to, nor do I want to change the fixtures. The other shower would be nearly impossible to access the back side, as the back side would be into the one-piece tub shower of the other bathroom.

So was doing some research and came across inline pressure balance valves. But not alot of info on how to install.

Basement is all open (unfinished) and I have access to all the plumbing. So some questions

1. Do I need one for each shower or will one work for both?
2. How well do they actually work being farther away from the shower?
3. If one will work, should it be mounted as close to where the two showers split off? Or closer to the waterheater/source? Or does it matter?

Any reccomendations on ones that are good? ones to avoid?

Paddy · Dec 8, 2016

I would imagine it's based on how complex your plumbing is. The entire principle of balance is last stop for the cold and hot. Any cold or hot coming off after the aftermarket balancing would defeat it.

I'd up grade the fixture where you have access. Bad layout on the other, at some point all fixtures will need servicing.

Raspy · Dec 8, 2016

Don't know if this would work for you, but it would be nice if you could run a new hot and cold directly to the master bath that didn't have drops along the way for the washer and other toilets. The lines would come from the water heater area where the cold tees to become hot and feeds on to supply all the colds.

LD1 · Dec 8, 2016

What would be the reason for new lines running to the master? What would that accomplish?

Why would nothing after the device get "pressure-balanced"?

If cold water is turned on at any faucet, before OR after the decvice, would cause a pressure drop in the WHOLE system. So I am not sure I understand the comment that it wouldnt balance if anything was turned on after.

As far as servicing the valves, yea, I aggre its a bad layout. But aside from sweating in a whole new fixture, any servicing or rebuilds of the mixer can all be done from the shower side.

BAsement plumbing is not complicated, but the way its laid out, it would be hard to put a balance valve in that "didnt" have something other than the shower downstream of it. Possible, yea I could probably put two devices in, one on each shower. But would be alot easier to just put one in. Which would put ALL the fixtures after it.

here is the basement.

See the pic of plumbing. Bathroom water has a hot and cold going to each bath. Somewhere up inside the wall is where it splits off for the toilets and sinks in the bath. So it would be inpossible from the basement, to put ANY device AFTER those but before the showers.

Square yellow boxes are potential places to install.
#1 would only cover master bath
#2 would cover BOTH bathrooms, including the sinks and toilets in those bathrooms, but nothing else
#3 would cover the whole house, which only adds the additional drops for the washer, and the run to the kitchen.

Raspy · Dec 8, 2016

LD1,

The reason for new lines, if it's an easy installation, is that if you have a 1/2" cold line, for instance, feeding the master bath, and on the way it also feeds the washing machine, when the washer comes on it has less pressure on the cold side, at the master, and the water at the shower will get hotter.

It seems most houses have the cold from the street going to a tee near the water heater. One side becomes cold for the whole house and the other becomes hot for the whole house. So, if new dedicated lines are run from that area, there can't be a pressure drop on only one of them, if the washer fills.

Since this is an existing house the line sizes are already in place. If they were larger, it might not be a problem in the first place. I ran 1" lines for most of my plumbing and ran separate supplies from a central source to the baths and kitchen. Temperature fluctuation has never been a problem.

LD1 · Dec 9, 2016

It's 3/4 copper plumbing to everything.

I don't think it matters much how the lines are plumbed and what sizes. If there is an additional draw on one side, it creates a temp change.

Thus my inquiry into the inline balance valve.

I just realized the pic never uploaded. Will have to try again when in get home in the morning.

Judging by the lack of responses it seems these aren't too common.

Really need to know if I just need 1 or 2, and where is the best place to install them.

LD1 · Dec 9, 2016

I edited my earlier post of the pics of the plumbing. For whatever reason my attachment didnt work yesterday.

teejk · Dec 9, 2016

I think any pressure balance mechanism I have ever see has been in a shower fixture where it can be easily accessed and adjusted if needed. I can't think of any other fixture where it would be needed. Whatever you decide on an "in-line" valve, I would make sure it could be accessed.

LD1 · Dec 10, 2016

teejk said:
I think any pressure balance mechanism I have ever see has been in a shower fixture where it can be easily accessed and adjusted if needed. I can't think of any other fixture where it would be needed. Whatever you decide on an "in-line" valve, I would make sure it could be accessed.

That is the reason for wanting to go with an inline valve.....is because I CANNOT easily access the shower fixtures. Main bath has a 1-piece tub-shower. The backside of it is in the master closet, and drywalled.

The master shower is a standup shower, backside of it....is the one-piece shower of the main.

Current fixtures do NOT have the pressure balance the house was built before they became the requirement and the "norm"

I have open access in the basement.

This is just a random one, and not the one I plan to buy as I havent researched much yet (was hoping for a little more feedback here), but something like this would be pretty easy to install in the basement In-Line Pressure Balancing Valve - Decor Island

But my questions remain.....is it best to get two and try to install as close to the showers as I can? Or a single one as close to the "pair" of showers? Or a single one back near the waterheater? OR does it even really matter?

I may install it back near the water heater, since its pex. When I installed my geothermal, it had a desuperheater that got tied into my hot water. And a second storage tank. So I plumbed everything in PEX, and tied back into the copper.

teejk · Dec 10, 2016

LD1 said:
That is the reason for wanting to go with an inline valve.....is because I CANNOT easily access the shower fixtures. Main bath has a 1-piece tub-shower. The backside of it is in the master closet, and drywalled.

The master shower is a standup shower, backside of it....is the one-piece shower of the main.

Current fixtures do NOT have the pressure balance the house was built before they became the requirement and the "norm"

I have open access in the basement.

This is just a random one, and not the one I plan to buy as I havent researched much yet (was hoping for a little more feedback here), but something like this would be pretty easy to install in the basement In-Line Pressure Balancing Valve - Decor Island

But my questions remain.....is it best to get two and try to install as close to the showers as I can? Or a single one as close to the "pair" of showers? Or a single one back near the waterheater? OR does it even really matter?

I may install it back near the water heater, since its pex. When I installed my geothermal, it had a desuperheater that got tied into my hot water. And a second storage tank. So I plumbed everything in PEX, and tied back into the copper.

My shower valves (Moen) grant access to the balance mechanism (more of a temp balancer than pressure) by removing the trim plate from the shower side. I'm pretty sure Delta and others are the same. I've done a lot of plumbing and have to say that I've never seen an in-line valve but I'll take a look at your link (I crave knowledge). I do recall seeing an article years ago about plumbing with a "water distribution ring" (essentially a manifold) but never knew anybody that used it.