Will a PRV pass low pressure?

[Mnoone]

If my PRV is set to 75PSI but the pressure coming in from the street (connected to PRV input) dips to 25 PSI, will the PRV's output go up to 25PSI? If not, what will it go to?

I ask because I'd like to hook up a small circulating pump temporarily to run hot water through my cold water lines. I'd be hooking this up to a hose bib that is on the inlet side of my PRV, and want it to flow through the PRV. Will this work?

 

[Reach4]

If during flow, when the input was 25 psi and the output was 23 psi, would that hurt your plan? I don't think so. In other words, I expect some pressure drop, but not a lot.

Also, some PRVs have the bypass feature. Water can be pushed thru in reverse, if you have one of those.

If your motivation is sanitizing, a pH-adjusted chlorine bleach solution will do a better job.

 

[Sponsor]

 

[Mnoone]

If during flow, when the input was 25 psi and the output was 23 psi, would that hurt your plan? I don't think so. In other words, I expect some pressure drop, but not a lot.

Also, some PRVs have the bypass feature. Water can be pushed thru in reverse, if you have one of those.

If your motivation is sanitizing, a pH-adjusted chlorine bleach solution will do a better job.

25 PSI was a made up number. I'm using this pump If there is a small pressure drop across the PRV I think it should be fine. PRV is a Watts PRV-34-LF25AUBSDUZ3. How do I tell if it has the bypass feature?

Motivation is mostly getting old flux out of lines. But cleaning in general seems like a good idea. I figured hot water would dissolve the flux. But I'm open to suggestions of a better solution to run through the lines!

 

[Reach4]

25 PSI was a made up number. I'm using this pump If there is a small pressure drop across the PRV I think it should be fine. PRV is a Watts PRV-34-LF25AUBSDUZ3. How do I tell if it has the bypass feature?

Motivation is mostly getting old flux out of lines. But cleaning in general seems like a good idea. I figured hot water would dissolve the flux. But I'm open to suggestions of a better solution to run through the lines!

The description would include the word "bypass" as https://www.watts.com/products/plum...ves/water-pressure-reducing-valves/lf25aub-z3 does.

Hot soapy water sounds good. Do you know what flux? Maybe experiment with that smeared, or baked, onto a test surface.

 

[Mnoone]

I used Oatey H20 flux. It is supposed to be water soluble but it seems to be very slow in that regard