How do water regulators work?

myredracer wrote:

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A good source for info. and purchase of regulators: http://www.rvwaterfilterstore.com/

The first entry on their regulator page is the US$24.95 Fairview 55psi. They seem pretty happy with it:

Expect little difference from what the spigot can put out. Not adjustable or repairable like the Watts units, but very economical with high performance

Anybody tried one of these?

Good info here. Have been so disappointed with the low flow rate of our water regulator, especially when taking a shower, that I prefer to use the pump and water tank.

Will look for an adjustable home regulator with gauge.

The diaphragm controlled by a spring device that myredracer talks about is also how your propane regulator works.

There are two types of regulators (aka pressure reducing valve - PRV).

One is the inline type that has a small hole in it (orifice) that is something like 1/32" - 1/16" dia. and is fixed in size. Some info.: orifice "regulator"

A problem with the inline "regulators" is that they are more of a flow restrictor and have a low flow rate of around 1 gpm. Also, because there is an open hole, when water is not running, the pressure fill eventually equalize on both sides of the regulator. If there is sustained high pressure on the inlet side, damage can be caused to the RV's system including filters if they have been added. RV-ers buy a lot of these because they are so inexpensive. You won't find a pressure vs flow rate chart for them though because they don't want you to know how they really perform.

The other has a diaphragm in it controlled by the pressure from a spring. The water pressure on the inlet/incoming side acts against the diaphragm and the diaphragm varies the size of the opening (restricting element) inside the regulator to control the pressure on the outlet side. These have good flow rates, but it depends on the particular model and physical size. Watts is a popular brand and their 560 and 263 series are often used in RVs. This model has a good flow rate for an RV of around 4 - 4.5gpm. Here is info. on the Watts 263A that shows the flow/pressure curve. Watts 263A

We have a Watts 263A inside our TT along with an inlet and outlet side pressure gauge. One of these days I am going to take our old inline regulator and vary the supply side pressure (we are on a well) and see how they two types compare.

Interestingly, they do make an orifice type regulator that has a flexible orifice size and provides better control: flexible orifice regulator

A good source for info. and purchase of regulators: http://www.rvwaterfilterstore.com/

I used to use the pre-set regulators that ran from 45-50 lbs. This year I bought an adjustable regulator with a gauge so that I can take advantage of pressure over 50 lbs. I have set it at 55 lbs. which is safe for RV plumbing. It is amazing what the extra 5 lbs. of pressure means for a shower, flushing and washing dishes. Feels just like home. Well worth it. BTW, if park pressure is less than what the regulator is set for it does not hinder the water flow. The regulator does not restrict pressure until it exceeds the limit it is set for. There is a diaphragm inside that regulates this.

Gbopp, Beemer,

Okay I think I get it. When the spring holding the intake water valve open is overcome by the water pressure acting on a diaphragm; the valve closes, the pressure drops, so the valve opens to let a little more water in.

Lot of stuff going on in that little tube. ;)

I can see where low water pressure flow would be restricted even more, trying to flowing through the regulator valve ports.

Fortunately it worked fine for us but our water demand is mostly cooking and washing dishes.

They operate with a spring load that is either preset or adjustable. When water is flowing it opens and closes rapidly to control the output pressure.

Water Pressure Regulator and how it works.

THey work really well.

There is a spring that closes off the water flow when the output pressure is over the set point.

The problem is they also restrict water flow when the campground pressure is less than 50 PSI, so it is best to not use it at less than 50 PSI, many forest campgrounds are low to save energy on pumping costs. I bought a pressure gauge already hooked to a garden hose fitting at Home Depot last week, $12. I can measure the pressure, then use the regulator if needed.

Someone mentioned using a home style regulator. Because I was living in one area for well over a year, I bought a 3/4" regulator and fittings to adapt to my PVC water line. Then I was not limited to about 2-3 GPM that the garden hose regulators limit you to. Also from Home Depot, you can buy 3/4" Male pipe to female garden hose fitting and a 3/4" garden hose bib for the outlet so it will be portable and can be used at campsites. You will also need a 3-4' long drinking water hose, so you don't have to hang the 3/4" regulator from the garden hose bib, it might not support the weight well.

Fred.

Good question. I've also wondered if they control pressure both with water flow, and no flow. Do they limit static pressure when there is no flow?