Water Pressure

I don't leave my hose lying out .............

Fill fresh water tank and then put hose away until needed to fill fresh water tank.

No hot hose!

myredracer wrote:
Psi inside your camper would remain the same as the incoming CG pressure. If you are thinking your hot hose could drive the pressure up from the CG faucet connection all the way through the municipal distribution system back to the water system source (dam, well, lake), not possible. If you had the CG faucet off, any pressure increase in the hose and RV piping would be insignificant.t.

Good points.

Psi inside your camper would remain the same as the incoming CG pressure. If you are thinking your hot hose could drive the pressure up from the CG faucet connection all the way through the municipal distribution system back to the water system source (dam, well, lake), not possible. If you had the CG faucet off, any pressure increase in the hose and RV piping would be insignificant.

RV hoses have different max. psi ratings. The pressure at which a hose will burst is affected by temp. and dia. of the hose. A smaller dia. 1/2" hose can withstand more pressure than 5/8". As a hose would heat up in the sun, the hose material would soften and expand, have it's pressure rating go down and at some psi would burst. The concern about high water pressure is what the CG system psi is. We've seen it as high as 140 psi so far and it has been reported by some as high as around 200 psi. RVs are supposed to be tested for at least 100 psi.

Cheapie hoses can have a rating as low as 40 psi like this standard Camco hose. RV drinking water hoses are available with a rating as high as 375 psi like this Valterra hose. We have a regulator inside our TT and use a heavy duty, high pressure 5/8" hose rated for 200 psi.

At the very least, you want a basic inline regulator at the pedestal faucet end of the hose. There are other better regulators available. If you put your regulator at the city water inlet, it would be wise to get a hose with high pressure rating. Always a good idea to have a spare drinking water hose, even if just for the times you need 50' or more to reach the faucet.

A few years ago we had a garden hose hooked up to the campground water spigot laying in the, almost, 100 degree sunlight. Didn't think anything about what was going on, until a neighbor camper walked up and suggested we look at our hose. So we did.

Um, a section of about 3 feet blew up like a hot-air balloon. It had to be at least 12 inches in diameter! Before I could make it to the spigot to turn the water off .... she blew! Split long ways, about 6 inches and what a wonderful shower flow of HOT water! I'm glad I witnessed the event, I would have never believed it otherwise.

That was one of many events that ultimately led me to never leaving the water hose connected to the trailer and spigot and left on. That, and unknown pressure coming out of that spigot at every campground we go to, we now fill our fresh water tank, pump from the on-board water pump, and keep the campground spigot turned off, except to fill the fresh water tank.

So yea, sitting in the sun can cause pressure to build, but the risk of busting your garden hose is greater the hotter it gets.

rv2go wrote:
I had never really thought of it this way. Maybe instead of putting the water pressure regulator at the pedestal, it would be better to put it at the RV water inlet.

I agree. I carry extra water hose and in 30-years I haven't lost one to water pressure yet. when we bought our new Suncruiser last year I had the dealer install a stainless steel Watts pressure regulator (left) and an additional Watts stainless pressure gauge (right) in the wet bay. that gauge monitors the inbound water pressure which can be adjusted at the other.

I would think the static pressure would go up just a bit, simliar to when you turn on the HW faucet after heating up the water heater tank - a short little blast. The hose will probably expand a bit too lessening the increase.

I can't imagine the temperature of the water increasing a large amount such that it would cause the pressure in the hose to increase much more than 3-4 PSI.

google says in a 40 gal water heater the volume would increase about 1/2 a gallon when the temperature has increased to 140. So thinking that hose contains (depending on length) less than a gallon of water... I wonder how much the pressure would really increase.

Bob Vaughn wrote:
As the sun heats up the hose and the water inside doesn't the pressure inside increase also ?

I've never noticed it, but I'm not in 100+ sun either.

The water regulator goes on the spigot, NOT the RV. You don't want system water pressure bulging your hose all day long.

Are we over-thinking this.
Probably best practice would be hook regulator at the pedestal and set it for around 45psi. This way the hose is protected AND there will be no worry about the pressure inside the rig...even if the hose does heat up some.

rv2go wrote:
Maybe instead of putting the water pressure regulator at the pedestal, it would be better to put it at the RV water inlet.

Always install a water pressure regulator at the source tap to protect not just the trailer from excessive pressure but also the potable water hose feeding it.