Proper water pressure for pressure reducing valve.

I am womdering what is appropriate water pressure for a 2400 sq ft two story house with a kithchen sink, dishwasher, half bath downstairs with a toilet and sink, downstairs laundry room with washing machine faucets, and two full upstairs baths each of which has double sinks. A plumber through a meter on the bib coming from the 1 inch feed for the house and it read a little less than 70, but that was with a slab leak, and he estimated that pressure may be more like 80 when the leak is corrected.

One reason I ask is we have to install expansion tanks when replacing the hot water heater and which one I get depends on whether pressure is 80 or greater. Also, it seems that a new reducer is a good idea as mine is 27 years old. As I understand it, the less the pressure the better for the pipes. but I don't want it set too low.

 

I would consider 50psi to be a good setting for an average home. (60psi.maximum)

 

Thanks. Then I will replace the 27 year old pressure reducer valve. I noticed about 6 months ago that water pressure seemed a lot higher at a sink that used to have low pressure. That should reduce some wear and tear on my pipes.

So I will go ahead and pick up one of these Watts. It looks simple enough to installl

 

Am I inviting trouble if I just adjust the pressure down on this 27 year old reducer valve, assuming it will adjust?

 

I would have a replacement on hand. Replacing it will ensure another decade or two of good regulation of the water pressure.

 

Thanks Chandler. I will pick one up at the same time I get a pressure gauge, in case the old one goes bad when I try to adjustt the pressure. Replacement looks simple enough if I can get one to match up with the original.

 

I went to the HD to get a reducer valve and a water pressure gauge. They are all sealed up, but to me it was unclear if any will slip in without some cutting of the main. I think what I have is a double union 1 inch brand unknown. Without undoing the unions I can't tell just what the gap in the main is, but I suspect it may be about 4 inches. With the unions on, the space is just about 3.5".

Does anyone have an idea as to what to buy for a slip in replacement. The pressure reading peaks just over 80 when the bib is turned on and immediately drops to about 68 psi measured with the hot water shut off at the hot water tank. Leaving the bib on I then opened the ball valve for the tank, and got no change in psi. (Perhaps a drop of 1 pound, that came back to 68 after the hot line may have tightened up a pinhole leak at a joint that opened up while I was working on isolating a 1/2" line of copper.)

I have a suspicion that there is no way to tell if the gap has to increased or decreased, until the couplings are backed off and pulled back.

 

You should be good to go with this one Zurn-Wilkins 3/4 in. x 3/4 in. Brass Water Pressure Reducing Valve-34-70XLDU - The Home Depot

You'll have to paint it white another day Just kidding.

 

Kidding is good. I just figured out why the plumber that has been playing games about giving us an estimate doesn't return phone calls. No license and I insisted that he pull a permit before starting work

I was looking at the box holding a Zurn-Wilkins at my HD, but I thought I needed a 1". The o.d. of the pipes to which the reducer couples on each side is 1.16", including the beautiful paint. The pipe coming up out of the mud sill behind the water heater is a 1" that immediately reduces to 3/4.

 

Meanwhile, I loosened the lock nut and backed the adjusting screw out pretty far, about 1/2", while monitoring the p.s.i. It didn't budge. Does that sound like the prv is frozen/no good?

 

Chandler. I hope you didn't think I was questioning your plumbing skills. It's just that the picture I posted may be misleading as to the size pipe which definitely has an o.d. of more than .3 inches than the 3/4 inside my home. I don't know, of course, if exterior 3/4 has much thicker walls than what may type m and I think m is what was used by the builder. If the walls for exposed exterior pipe are even greater that L I imagine it could be 3/4 i.d.

I have left the p.s.i. gauge on that bib for a couple of hours now and then opened up 4 hot water taps. Pressure dropped by about 6 pounds and returned to 67 when I closed the taps.

 

Plumber? Heck no, I'm a naildriver, but I did stay in a Holiday..........I was going on nominal sizes. 1" are also available. Zurn-Wilkins 1 in. Lead-Free Bronze Water Pressure Reducing Valve with Double Union Female Copper Sweat-1-70XLDUC - The Home Depot

However holding 67 psi is well within normalcy, so you may not need a replacement

 

Hi, How about getting a rebuild kit? The tag on the top should have brand and model and maybe size.
I rebuilt mine about 3 years ago. Pretty easy job. Took about an hour would take longer if you forget to shut off the water.Mine is a Wilkins model 600 1". Got it on the internet about $60.00
Good Luck Woodbutcher