Higher than preferred water pressure..

[Rsaybe]

Hello, my existing water pressure is currently at 80 to 85psi. I'm feeling that this is a little higher than were it should be. I would rather see this down to at least 60 or 65psi.

Interestingly I had our main city water shut off valve replaced about a week ago and at the time I had mentioned my concerns over the high pressure readings my gauges are showing. The tech mentioned that I shouldn't feel concerned about those readings and that he's seen other residential areas upwards of 100psi.

Gez, that wasn't comforting at all to say the least.


Nonetheless I went online and decided to look into a PRV valve. Looks like most valves are like a check valve and preventing any pressures from going back into the city main thus requiring an expansion tank.


However I did find a few PRV valves that are designed to let water back into the city thus not requiring an expansion tank.

These are the valves I found that has this feature as noted below,

Watts LF25AUB-Z3
Cash Acme EB-25

I have a tankless electric water heater and my main plumbing is sized at 3/4".

Was hoping someone with a little more knowledge and or familiarity with these valves can let me know if these particular valves would work without having to install an expansion tank?


Also, what would be the most ideal location to install this valve?

I took a photo showing my plumbing layout and were I thought would be an ideal location to install a PRV valve although I believe both my existing check valves would defeat the purpose of these types of PRV valves as they wouldn't allow the water back into the main.

The area where I noted "PRV Valve Here" is my main cold water line coming in through my garage. Should I not have any check valves installed when using this type of PRV valve?

Any suggestions or help in getting this correctly set up would be much appreciated.

 

[Reach4]

Many municipalities are adding check valves at the water meter, at least when they swap out the meters.

In your diagram, things confuse me. Where does the water enter? At a elbow above a blue bucket at the bottom? And if so, what is that pipe that connects before the shut off valve?

I would note that in your softener loop, it looks like the left side would be the input line, and the right side the output. If that is the case, your connectors to most softeners would need to crisscross.

 

[Sponsor]

 

[John Gayewski]

A tankless water heater in practice doesn't really need an expansion tank. You should add an expansion tank anyway when adding a prv. Those prv's with a bypass your looking at don't make very much sense anyway.

Prv's fail all of the time so install it in a place that it can easily be changed and away from your water heater. It should be one of the first things on your cold water pipe as it enters the house.

 

[Rsaybe]

Many municipalities are adding check valves at the water meter, at least when they swap out the meters.

I had my meter swapped out a few years back (about 3 years ago). I don't believe I noticed any check valves in the area.

In your diagram, things confuse me. Where does the water enter? At a elbow above a blue bucket at the bottom? And if so, what is that pipe that connects before the shut off valve?

About the diagram, yes the water enters from that elbow above the blue bucket you see there. That other pipe you see below the shut off valve is the filtered cold water return back into the house through the crawl space.

I know the angle of that photo I previously posted doesn't show that very well. I took another shot with more of an angle side view so you would be able to better see those mentioned areas.

I would note that in your softener loop, it looks like the left side would be the input line, and the right side the output. If that is the case, your connectors to most softeners would need to crisscross.

About the water softer inlet and outlet, on the back of my water softener the inlet is on the left side and outlet is on the right side. I included a photo showing it's direction.

 

[Rsaybe]

A tankless water heater in practice doesn't really need an expansion tank. You should add an expansion tank anyway when adding a prv. Those prv's with a bypass your looking at don't make very much sense anyway.

Prv's fail all of the time so install it in a place that it can easily be changed and away from your water heater. It should be one of the first things on your cold water pipe as it enters the house.

Thanks for your reply John, I wasn't aware about not really needing to have an expansion tank for tankless water heaters. Is that because the hot water only occurs on demand and there's no actual storage of water still heating up even after the faucet is turned off (thus no pressure building up)?

I'm still trying to understand how those PRV valves would work if I have check valves installed. The PRV valves with the bypass features couldn't work as intended if I have the one way check valves installed. Is this correct?

Or am I viewing this all wrong?

Does a check valve also creates a closed loop system?

I took a close up shot of my pressure gauge showing my current reading.

Is this considered high enough to create problems for my plumbing or appliances?

 

[Reach4]

OK on the softener. The Fleck, Clack, and some others go the other way. Your bypass leaves no doubt in your case.

I believe 130 is not enough to cause problems, but some would disagree with me, thinking that exceeding 80 psi is a problem.

Here are some threads where I discussed my logic.

https://terrylove.com/forums/index....ank-operating-as-designed.105633/#post-754348
https://terrylove.com/forums/index....ssure-gauge-question.95806/page-2#post-699190
https://terrylove.com/forums/index....ure-in-water-heater.100851/page-2#post-725523

https://terrylove.com/forums/index....ting-electric-water-heater.96359/#post-693287

 

[Rsaybe]

Thanks for sharing those links. I have also seen info online mostly saying as long as the pressure is not exceeding 80 psi. And my pressure is hoovering around there. 80 to 85psi. This may not be considered extreme and is very well why the city worker said I shouldn't be so worried however I would feel better if I had my pressure more around 70-75.


It seems like a 10 psi drop wouldn't make much difference in the pressure we feel coming out of our faucets but may very well help as to not exert more than necessary pressure on our appliances, faucet cartridges
and or seals.


If I were to install a PRV valve like the Watts LF25AUB-Z3 (which I mentioned above), would it be preferable or suggested to do so before my check valves?

 

[John Gayewski]

Here's a sharkbite that blew apart. I can't help but notice you have a lot of those.

Any plumbing fixture in the world is made to be used at 80psi or under. Pressurea above that does indeed cause stress and undo wear and tear.

I would install a high quality prv.

 

[Reach4]

I don't know the function of your check valves. PRV would go after the main shutoff valve, and maybe before the water splits off for the outside spigots/irrigation.

 

[Rsaybe]

Here's a sharkbite that blew apart. I can't help but notice you have a lot of those.

Any plumbing fixture in the world is made to be used at 80psi or under. Pressurea above that does indeed cause stress and undo wear and tear.

I would install a high quality prv.
View attachment 101303

I was a little apprehensive using sharkbits although I made sure to use it only in that small area inside our garage and nowhere else.

I replaced my entire house plumbing from galvanized to copper (except for the garage area connecting to my water heater and washing machine) about 17 years ago. All soldered joints and to this day they are all holding up well.

Just over the past few weeks I finally pulled the last of the galvanized out of the garage and installed the copper. Again soldered all joints which will be inside the wall and (for the first time) used the sharkbites only in that exposed area.

Thinking about it now It would have been just as simple and cheaper to have soldered all those external joints as opposed to using the sharkbites. I may one day end up having to replace all those sharkbites.



Is the Watts LF25AUB-Z3 prv considered a high quality valve? Would there be another one that may be better suited for my application?

As initially mentioned above, I have a tankless electric heater and not intending on using an expansion tank and did like the idea of how this particular watts valve would let water back into the city as necessary.

I would prefer to use one that has a double solder union.

 

[Fitter30]

Even if the down stream pressure could it wouldn't it would have to be higher. So instead of adding a expansion tank you would rather have the hot water heater expansion be controlled by the reducing valve. So all the fixtures , clothes washer and dishwasher be under the control of the reducing valve. Because the only way the reducing pressure is going backwards has to over come incoming line pressure.

 

[Rsaybe]

I don't know the function of your check valves. PRV would go after the main shutoff valve, and maybe before the water splits off for the outside spigots/irrigation.

In my home the main water line comes through my crawlspace and then branches out into two sections. One line runs straight through to our outdoor spigots and the other line (tees off) goes into the garage where it then passes through the whole house filter and then tankless water heater and back down through the crawl space and distributed throughout the house.

I don't mind the pressure being a little higher (as it is now) for the line that runs to my outdoor spigots.

If you look back at my first photo were I noted "PRV Valve Here", that would be the main line that enters our home through the crawlspace. Would this be considered an OK location?

That would be right before my check valve. I had planned on putting it right after that shut off valve you see in the bottom of the photo.

Sounds like this would work well?


Hope my description didn't confuse you much.

 

[Reach4]

It would be shutoff valve first. Then PRV somewhat later. It makes no sense to me to go for a bypass PRV and then put a check valve in line with that. I think that a non-bypass PRV also has a check valve function, at least AFAIK.

If putting in a PRV, you would want to opt for one with dual unions. That way you could swap out the PRV in the future.

Sharkbite has some interesting PRVs IMO.

 

[Rsaybe]

Even if the down stream pressure could it wouldn't it would have to be higher. So instead of adding a expansion tank you would rather have the hot water heater expansion be controlled by the reducing valve. So all the fixtures , clothes washer and dishwasher be under the control of the reducing valve. Because the only way the reducing pressure is going backwards has to over come incoming line pressure.

I see what your saying.

You got me thinking, so If I were to use this type of bypass PRV which allows water to flow back into the city, the acting pressure against the main upstream would have to be greater than my city pressure to let the water go back.


And given that I'm using a tankless water heater with no storage unit the likelihood of any thermal expansion causing an excess in pressure to be high enough to make the water go back into the city is low (or just not likely to happen).

Am I viewing or understanding this correctly?

 

[Rsaybe]

It would be shutoff valve first.

Got it. So will put the prv after that shut off valve.

It makes no sense to me to go for a bypass PRV and then put a check valve in line with that.

I'm beginning to see what your saying about having a bypass prv with my check valves in front of it. Seems like both those check valves would defeat the purpose of any bypass feature on a prv?


Looking over my layout, I'm not sure why we even installed the first checkvalve directly after the shut off valve (as seen in the first photo up from the blue bucket). I drew this layout on paper about two years ago. Don't know what I was thinking or drinking.


The second checkvalve right before the cold line enters the water heater was intended to keep any heated water from possibly flowing back into the cold side. Not sure if this is required although I do recall reading up about something like this as being suggested.

Maybe we should just remove both those check valves and then maybe the bypass prv would make more sense?

Looking online today I found out they actually make these small tennis ball sized expansion tanks for tankless water heaters.

Water Heater Expansion Tank for Tankless Water Heaters


Didn't know they made them this small. I got to thinking that I can add this in place of that check valve (the one before the tankles water heater).

Would this be a good idea?

If putting in a PRV, you would want to opt for one with dual unions. That way you could swap out the PRV in the future.

Yes, one thing for certain is that I will use a double union type for ease of simplicity for any future replacements.

I'm veering more towards the soldered joints from here on.

 

[Reach4]

I'm veering more towards the soldered joints from here on.

Read up on "press" for joining copper. Very popular. It can be done with a hand tool or a power tool.

 

[Rsaybe]

Read up on "press" for joining copper. Very popular. It can be done with a hand tool or a power tool.

I'm familiar with press fittings. I had actually purchased a ridgid press tool with both 1/2" and 3/4" jaws from Zoro about 2 years ago only to return it back less than a month later.

Like sharkbite they also relied on that o-ring to maintain a water tight seal. I opted for sharkbite as I can quickly remove the fitting to install my drywall and then reuse again, unlike with the propress fitting.

Although once I get the drywall up, I may replace those few external sharkbite fittings with soldered joints just for the peace of mind.

 

[Rsaybe]

Does anybody have any experience on the small sized expansion tanks I linked in my previous message?

Are these any good?

I wouldn't mind installing one of those tennis ball sized units as they have a very small footprint which would work for me...


I also saw this other one similar to the first one I posted.


Second Water Heater Expansion Tank for Tankless Water Heaters

Looks like this one has a schrader valve.

 

[John Gayewski]

Does anybody have any experience on the small sized expansion tanks I linked in my previous message?

Are these any good?

I wouldn't mind installing one of those tennis ball sized units as they have a very small footprint which would work for me...


I also saw this other one similar to the first one I posted.


Second Water Heater Expansion Tank for Tankless Water Heaters

Looks like this one has a schrader valve.

The only reason they exist is to satisfy the requirement for an expansion tank in a closed loop when a tankless is used. They are fine more like a hammer arrester than an expansion tank.

 

[Rsaybe]

The only reason they exist is to satisfy the requirement for an expansion tank in a closed loop when a tankless is used. They are fine more like a hammer arrester than an expansion tank.

Funny, yes, I guess they kind of are like a hammer arrester. I'll add one to the system. It might help.


About me adding a PRV to my system, I feel that watts makes some good quality products. would the one I mentioned previously be considered a high quality prv?

I included a link to the PRV I was looking at. The pricing is about were I like to be for this type of unit as well.

Lead-Free Brass Pressure Reducing Valve

Any thoughts or other suggestions?