Pex piping....do I need a regulator?

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DeckArtist

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Elmo, Texas
Not sure if this piping was standard in '02, but some of it looks factory, especially what was under the mini-tub shower. Do I need to get a regulator if there's not one by the old HW heater?
 
Regulators are for the entire system, the piping or tubing is only one part of it. Water heaters, lavatory fixtures, outdoor showers, clothes washers, everything is impacted. So if hooked up to outside water sources, a surge can cause problems even if the pex can handle it.
 
I use an inexpensive fixed pressure inline one (40PSI?) at the spigot. I've had garden hoses burst at home so figure having one at the spigot protects the fresh hose to some extent too. Easy, cheap, I just leave it on the end of the hose. No idea if it really helps but it likely can't hurt.

Mark B.
Albuquerque, NM
 
I use an inexpensive fixed pressure inline one (40PSI?) at the spigot. I've had garden hoses burst at home so figure having one at the spigot protects the fresh hose to some extent too. Easy, cheap, I just leave it on the end of the hose. No idea if it really helps but it likely can't hurt.

Mark B.
Albuquerque, NM
I'm with Mark here. I gave up on the expensive regulators after the 2nd one froze. Where I camp in the spring/summer it's possible to get a couple of hours of freezing temps in the mornings. Doesn't seem to take much of that to destroy the gauges on the expensive ones.
The cheapy is just a flow restrictor and will work fine after it thaws out.
 
I'm with Mark here. I gave up on the expensive regulators after the 2nd one froze. Where I camp in the spring/summer it's possible to get a couple of hours of freezing temps in the mornings. Doesn't seem to take much of that to destroy the gauges on the expensive ones.
The cheapy is just a flow restrictor and will work fine after it thaws out.
You say it’s only a flow restrictor so does that mean it does not lower the pressure at all or little?
 
Pex has been standard for a long time in RV/s and yes you do need a regulator.
NOT for the PEX but for other things

I've been in a park where they measured pressure at 120PSI+ you NEED a regulator
Now regulators come in assorted flavors.. Most RV stores and RV departments sell a little cylinde thing about 3/4" in diamater (Size of a hose fitting)( leave it hang right where it hangs and walk on by.
Valterra Adjustable. I'm told is decent (Never used)
I had both a Watts and a Zurin 3/4 inch in-line regulator with hose fittings attached (They hose fittings are normally sold seperatly but some stores have the in a "kit" and those were impressive.
Set to 50 PSI. at no flow or full shower flow. still at 50 PSI (The cylinder would be closer to 5 at full flow)
 
You say it’s only a flow restrictor so does that mean it does not lower the pressure at all or little?
Not sure if it lowers pressure or just flow, since there's no gauge. I'm speaking of the cheapo "regulators" they sell at Wally World or in the hardware store RV isle that everyone tells the newbie's not to use.
 
This is the one I have.

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I have a similar one on my drip system for my garden, not so much for protection but the drip spouts are calibrated for a certain pressure. I've never put a gauge on it or the RV but they give the appearance of doing something - the pressure seems less coming straight out of the hose judging by flow and strength.

Mark B.
Albuquerque, NM
 
You say it’s only a flow restrictor so does that mean it does not lower the pressure at all or little?
The water pressure regulators are not designed to be flow restrictors although some of them do have that effect. A flow restriction does lower the pressure as long as water is running but as soon as you turn off the faucets the pressure will rise to whatever the supply pressure is. A true pressure regulator will prevent that from happening. The reason that the cheapest regulators also restrict the flow is that they have a smaller water passage diameter than your water lines have. The cheapest water pressure regulators have a water passage of only 1/4" while the better ones are 1/2" or larger with home water pressure regulators having 3/4" or greater passage diameters.
 
The water pressure regulators are not designed to be flow restrictors although some of them do have that effect. A flow restriction does lower the pressure as long as water is running but as soon as you turn off the faucets the pressure will rise to whatever the supply pressure is. A true pressure regulator will prevent that from happening. The reason that the cheapest regulators also restrict the flow is that they have a smaller water passage diameter than your water lines have. The cheapest water pressure regulators have a water passage of only 1/4" while the better ones are 1/2" or larger with home water pressure regulators having 3/4" or greater passage diameters.
That’s what I thought all the time. Thanks Kirk
 
Ok good to know. I will get one. I will be connected directly to my own water meter next door when I get there.
 
You say it’s only a flow restrictor so does that mean it does not lower the pressure at all or little?
Some of those only "restrict" any pressure when the water is flowing - otherwise they are just an open tube with a small washer to impede the flow - so pressure can build up everywhere in the system. (Flow-Through-Washer)

Others do have a spring loaded brass diagram that does (modestly) regulated the pressure in a nice, compact design.

I've always been amazed that they sell the flow-through-washer design as pressure regulators when I can see daylight through them axially.
 
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I've always been amazed that they sell the flow-through-washer design as pressure regulators when I can see daylight through them axially
While I don't know what regulator you refer to, I have used several regulators of various brands over the years and I have never seen one like you describe. At present I use a Valterra RV Hi-Flow Water Regulator, that I bought from Amazon, but I have also used one from Camco and possibly other brands as I have been using them for a lot of years.
61eyGVL8tQL._AC_UL232_SR232,232_.jpg

I also keep a pressure gage on the inlet to our RV so that I know if the regulator is working as most of them do eventually fail, usually to the low pressure side. I use a gage that saves the highest pressure it sees so that I'll know what has been happening. I probably don't check it as often as I should but........
1675356116130.png
51mWtLYbgYL._AC_UL232_SR232,232_.jpg

I also keep one like the second gage (cheaper) on the hose bib that I am connected to. It's all probably overkill, but after a career in tech stuff I just want to know things like that. :unsure:
 
You spelled actually wrong. ;)
Not so. Axially means through the center like an axle.

I've always been amazed that they sell the flow-through-washer design as pressure regulators when I can see daylight through them axially.
That doesn't necessarily condemn them. When you're looking through one it's disconnected with zero pressure at it's output. The question is does it close completely when the output pressure reaches the regulator's rating.
 
You spelled actually wrong. ;)
LOL - I'm guessing you're kidding, since all the members do cajole and rib each other... And, yes - I do prefer cajun ribs (Double LOL) over a plate full of cajole and rib.)

For those that may be confused... axially is if you look along the length of a tube - (radially would be if you look from the side at the wall of the tube - as in radius).

If I hold those flow-through-washer "pressure regulators" as if I was pretending it was a telescope I can see daylight. At that same time I would actually be looking axially through the telescope.

Looks like it might be one of those days on the forum...
 
Not so. Axially means through the center like an axle.


That doesn't necessarily condemn them. When you're looking through one it's disconnected with zero pressure at it's output. The question is does it close completely when the output pressure reaches the regulator's rating.
I pulled the internal rubber washer out of one of the flow-through-washer kind. (Not the hose bib washer - the one on the inside that doesn't touch the hose or hose bib) Not much magic - just a rubber washer with a hole. No valve, no flapper ... perhaps I missed the concept entirely or the one I had was missing parts (from Camping World when I was younger, but still as naive as now).
 
Geeze, didn't mean to start the regulator wars. :rolleyes:
I just got tired of ruining the gauges on those $40 actual regulators that have diaphragms and went back to the flow restrictor type like Mark pictured.
 
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