High water pressure and PRV: need recommendation please

[JasonY]

Long story short, my public water supply from street is at 110 psi, and I don't have any pressure reducing valve currently in the house. Am planning to install one. I understand that even the PRV has a bypass valve, I need to also install an expansion tank on the cold line downstream (house side) of the PRV. My problem is as follows:

The water coming on from street has quite a bit coarse sediment, I can see it from the whole house water filter housing (translucent). Aside from the sand particles, there are larger pieces 1/16 to 1/8 inch. Apparently they go thru water meter just fine. But I worry so much about the sediment clogging the PRV if I install it upstream (city side) of the water filter. My water filter is an aqua-pure PT11 model, with max pressure of 125 psi. So far so good, knock on wood, but there's little margin. The PRV I ordered is a Wilkins 70XL, which hasn't arrived yet.

1. in your experience, is it OK to install the PRV upstream (city side) of the filter?
2. is there a good, heavy duty (150psi) water filter I can buy so that I can install PRV downstream (house side) of the filter?
3. what's the best solution for this scenario?

Thanks.

 

[Reach4]

Zurn SXL strainer is good for high presures. It is shown in the diagram at the bottom of

https://www.zurn.com/media-library/web_documents/pdfs/specsheets/reg-70xl-pdf

https://www.homedepot.com/p/Zurn-Wilkins-1-in-Brass-FPT-Strainer-1-SXL/202642509

 

[Sponsor]

 

[JasonY]

Reach4, thanks for the advice. That's Y strainer should work. but I'll need a 3/4 inch one, as my pipe is 3/4 in (OD=0.875inch). Local stores don't carry them. Homedepot only has the 1 inch strainer.... going online.

 

[Jadnashua]

Any filter/strainer will need to be cleaned/replaced periodically. The worse your supply issue, the more often.

A PRV with a bypass can't open to allow back flow until the house pressure on one side exceeds the supply pressure on the other...so, without an expansion tank, when the WH runs, your internal water pressure will still get to above that 110psi...not really what you want. With a properly installed ET, the pressure should remain essentially constant. If your utility has a check valve on your inlet, the relief valve can't do anything, and your pressure can spike to 150psi and cause the T&P valve to open. If your utility hasn't installed a check valve yet, over time, they are likely to as it is needed to protect the supply. Some places are just slower to do this than others, but it's coming.

A larger strainer might not need to be cleaned as often, so using adapters to the 1" on either side might actually help.

 

[JasonY]

I drew the diagrams of the current setup and the setting that i am planning (bottom of the picture).
Sorry how do i post picture?

 

[Jadnashua]

Sorry how do i post picture?

Click on the "Upload a File" button.

 

[JasonY]

here it is. current setting on top, planned at bottom. I also plan to use soldering on high pressure side (street pressure), and use sharkbite on the low pressure side (downstream of the PRV). The pipe is 3/4 inch. I already bought 3/4 inch strainer, so will clean that out when I do the water filter cartridge, usually 6 months. Please audit my plan, see if anything is wrong. Thanks.

 

[Reach4]

To solder, you will have to get the water out. Your valve before the meter might have a drain port to let you drain water.

Consider a 3-valve bypass around your cartridge water filter, or at least keep a spare 0-ring on hand.

 

[JasonY]

Thanks for the comment and suggestions thus far. 3-valve bypass sounds good.... I did not plan to touch the water filter initially... might as well do it.
I have a hand pump, can pump water out before soldering.... thanks. Question for Reach4, where do they sell separate O-ring for filter housing?

 

[Reach4]

I have a hand pump, can pump water out before soldering.... thanks. Question for Reach4, where do they sell separate O-ring for filter housing?

Depends on the filter.

My Pentek Big Blue housing uses Pentek O-ring 151122
I think this can be replaced by Ace Hardware 4001756 or Ace 49561, American Plumber W 10-OR and 152032. 151122, UPC 33663005082, Culligan OR-100

Your filter may use a different o-ring. I lightly lube my o-ring and any seal I deal with with Molykote 111. A 5.3 ounce tube lasts a long long time.




Somebody wrote "The oring itself actually measures approximately 5.465 inch (inside diameter)." I did not measure myself.

 

[JasonY]

Hi, Reach4. My filter model is Aqua Pure AP11T, I will try to find the O-ring part number. Thanks for the tip of lubing the O-ring.

 

[JasonY]

while waiting for the parts to arrive, I sized up the expansion tank. Local store has the Amtrol Therm-X-trol brand, and based on 50 Gal water heater, and temp settings, they recommend a 3.2 gal ST-8 model. Also I am thinking about the connections. One question on the MNPT and FNPT fittings, how tight do you go for a leak free connection? Below is the latest plan adding the 3-valve bypass (bottom half of the page). Thanks.

 

[Valveman]

while waiting for the parts to arrive, I sized up the expansion tank. Local store has the Amtrol Therm-X-trol brand, and based on 50 Gal water heater, and temp settings, they recommend a 3.2 gal ST-8 model. Also I am thinking about the connections. One question on the MNPT and FNPT fittings, how tight do you go for a leak free connection? Below is the latest plan adding the 3-valve bypass (bottom half of the page). Thanks.

With Teflon tape or pipe dope you shouldn't have to get it as tight. But there really are no torque specs, just tighten enough it doesn't leak and quit tightening just before you twist something off.