Looking for low water pressure diagnosis

[Dreamnair]

We have a low water pressure problem in our '99 Excella:

1. Kitchen and sink faucets run a steady, but weak, stream, whether on city water or the pump.
2. Shower pressure is so low (city or pump) that we can barely get water out of the shower head.
3. The Shureflo inlet valve leaks slightly, but there are no other leaks in the AS, at least so far as I can see. No water appears on the ground below or around the trailer (except the slow leak at the inlet valve).
4. All strainer screens have been cleaned or replaced.
5. With the inlet valve removed from the system and connected to city water we get a steady steam on the discharge side.
6. This trailer has been in south Texas for the last several years and probably has not been winterized recently. There is some evidence that it made its debut in Washington state, though, and may have spent some time in Alaska. (Possible leftover winterizing problems?)
7. Water heater appears to function normally, so valves should be in proper position.

Could there be a partially closed valve somewhere? Is there an inline filter that would affect city water pressure?

Since flow at the faucets may be normal (with pressure regulated), is it possible that we have a blockage at the shower valve?

In trying to interpret the piping schematics (and searching our trailer), there appear to be no valves that would affect pressure, and no filters other than the one at the pump.

Would appreciate any insight you can pass on with where our problem(s) might be.

John

[Nuvite-F]

Hi, John,

Afraid I can't help you much but I do have some questions on your diagnostic comments.

It appears that you have a restriction somewhere in the system, probably cold water side before the water heater, since pressure is low on both hot and cold water.

Unfortunately this could be just about anything. Your Airstream is probably plumbed with some kind of plastic tubing, which, in addition to actual obstructions, can be pinched or kinked somewhere, resulting in a flow restriction.

In fixing a low flow problem in the kitchen cold water faucet of our 1980 Caravelle I discovered a sheet metal screw had somehow found its way into the water line and lodged in a right-angle fitting, almost completely cutting off the flow. Could be something like that.

Originally Posted by Dreamnair

With the inlet valve removed from the system and connected to city water we get a steady steam on the discharge side.

I am assuming your inlet valve is a combination check valve and pressure regulator. (We have such a valve in the Carvelle, made by Watts Regulator rather than Shur-flo.) Now, what you're saying here is that if you remove the valve and connect it to city water, out of the trailer on the bench, plenty of water flows through it? How about the pressure at the outlet? If the regulator valve was regulating at too low pressure, for example 5 or 10 PSI, there would still be plenty of flow at open discharge but not enough pressure to overcome the pipe friction in the trailer. You might try measuring the discharge pressure.

Originally Posted by Dreamnair

Since flow at the faucets may be normal (with pressure regulated), is it possible that we have a blockage at the shower valve?

Are you saying here that you're not really sure how much flow to expect out of the kitchen faucets? The answer to that question is that when you are connected to city water you should get as much flow as you would get in your kitchen sink at home. I would guess 2 - 3 gallons per minute with the faucet wide open. And not a whole lot less than that running on the pump. This assumes that all screens are clean like you said.

Something you might try is connecting to city water and opening the low point drain valves (the ones used for winterizing) and see if water flows briskly out of them. If so they are before the restriction.

Somehow you have to figure out where the flow is being restricted. One clue you already have is that since the flow is low either on the city water and the pump, the restriction must be somewhere in the system common to both sources. (Either that or both the inlet valve and the pump are bad.)

Good luck--problems like you describe can be a real pain to track down.

Best of luck,
Nuvi

[redstart]

one simple thing to check - on our 1998 34' there is a push button on the shower head that turns off the water without turning off the tap. yours might be partially closed? the button is small, diameter of a pea. It should be pushed all the way to one side - on the one side it's closed and on the other, it's open.

[lynn]

Obviously you have checked for any leaks and all low point drainvalves are completely closed. The pressure regulator on your trailer if original is only 50 psi.You can change to a 65psi regulator.Make sure the screen is clean on the regulator inlet. The fresh water tank has a filter installed at the fresh tank out let fitting which keeps shavings from getting into lines from the tank,it should clean itself during travel.Also all faucets had flow restictions that limited water flow for conservation sake. If you have the same restrictions on pump and city water start looking where the pump and city water lines join the main plumbing sytem--should be close to pump area.

[Dreamnair]

Great comments, as usual from the Forum. I will check the outlet pressure on the inlet valve.

Our shower head also has a cutoff--in this case we get no water at all with the cutoff open and very little water with it closed. If we put the shower head on the floor, we get no water at all. We know the shower head and hose are working properly; they've been tested by connecting directly to city water.

My suspicions are on the inlet valve. If AS piping will handle 65 psi, upgrading to a higher regulated pressure might be my solution.

John

[Dreamnair]

To kinda close this one out, here's what I found out in diagnosing our low water pressure problems:

1. The shower hose appears to be the problem in our case. It's old and tends to kink at the top and bottom near the fittings. It's enough to close off the stream almost entirely when the shower head is on the floor.
2. Even though we'd cleaned the faucet screens, a complete replacement made an improvement.

When we tried to replace the shower hose we went backward...water wouldn't pass through it at all. We're now convinced that it's the vacuum breaker on most of these hoses that may be the culprit.

If anyone has any insight as to how the check valve at the inlet and any downstream vacuum breakers work (or don't work) together we'd like to hear it.

Thanks,
John

[carmelo]

A simple item to check is the screen on each fixture. Minute amounts of crud can and will cause the symptoms that you mention.
Remove each screen, often they are in several peices so note how they come apart so that after cleaning they can be re-installed properly.
CCC

[connorsa]

Could I please throw in my issue here as I'm working on it today. I have a hot water pressure problem only. The cold is great. I'm F-timing, hooked up to city water. The hot water pressure is bad on all faucets. We turned off the valve in the bathroom under the lav and are researching. I went in and looked at it and this little valve we shut off is leaking a little bit...

Our hot water is hot, it just has very little pressure. We're using electricity.

Thanks! Anne

[Dreamnair]

Have you checked the valves associated with the water heater. I think there are three of them (to allow a by-pass). If the in-line valves are partly closed this could be your problem. If you have a leak in one, that could mean corrosion or a partly-closed valve.

John

[connorsa]

A neighbor came over and by golly, took off one of the valves and removed the little O rings. Put it all back together and it works great! I guess the O rings could cause antifreeze to get into the hot water tank, but I won't be winterizing anyways for some time as I'm F Timing anyways. So yeah!