Deteriorating Water Flow- Exhausted Troubleshooting

BigHorns

Member
I have been fighting the proverbial water flow problem for several months and am finally crying uncle. I do understand the difference in issues of pressure vs. flow rate.


My pressure regulator at the spigot (the good Valterra unit with gauge- not the cheap one) will read over 80 PSI currently before I dial it back to around 50-55. I have another gauge at the connection in the UDC which typically reads 43 PSI (after a simple inline filter). These readings with a closed system, of course.


Turn a faucet on- anywhere, or open the toilet valve, and I get a rush of good pressure/flow for a couple seconds and within, maybe, 10 seconds, I've got a tiny stream.


From the spigot I have: spigot -> Valterra regulator/gauge -> 4-way brass splitter -> inline filter -> hose to UDC. All the 4-way connections are closed except the one in use here. Some example flow rates from testing filling a half gallon bottle:


  • 45 secs to fill the bottle from the kitchen sink faucet
  • 20 secs to fill the bottle straight from the hose otherwise connected to the Andersen Valve in the UDC.
  • 8 secs to fill the bottle through the same hose but with the inline filter removed.
  • 42 secs to fill the bottle from the kitchen sink faucet with the inline filter removed.


I also pulled the Andersen Valve out and filled the bottle directly from its city water port- it overflowed it in nothing flat.


Every indication is that there is an obstruction in my in-house system. But if there was, pressure should remain higher between the spigot and UDC gauges while water is flowing but it does not. Also implied would be a leak in the system. I'm dry as a bone inside, in the belly (I've pulled access panels), and on the ground. And with a leak, system pressure would not return as soon as you close an open valve.


Other notables:
  • This has been an issue in multiple parks with, ironically, unusually high water pressure,
  • I generally use a RV Water Filter Store 3-filter setup with their softener; they are not in the system currently,
  • I have disconnected/examined numerous pex half-inch threaded connectors. I don't have an ounce of corrosion exhibited anywhere. Also removed the screen filter in front of the onboard pump- it is crystal clear,
  • Other resort guests do not have the issue.


And, finally, this whole scenario occurs both on city water and on the onboard pump from the fresh tank. And it has deteriorated to this point only in last couple months. Been in the rig 18 mos.


I'm lost. Any ideas on what I'm missing or misinterpreting?

...Bill
 

wdk450

Well-known member
I would suggest that you disconnect the cold water PEX at the faucet farthest from the water inlet, disconnect the main water feed to the system at the Anderson valve, and using an air compressor try to blow out the line from the faucet end (backflow). There will be water from the
PEX tubes shooting out of the water supply end, so rig up an extension hose, water pail, or a lot of rags to cover this. You will probably want some rags/towels at the end where you apply the compressed air, too.
 

TedS

Well-known member
Check the faucet screens for signs of debris.

Also, it sounds like what happens when an accumulator discharges. Is there an accumulator installed? That would indicate general plumbing downstream of the accumulator is ok and the problem is somewhere near the inlet of the system.
 

BigHorns

Member
I would suggest that you disconnect the cold water PEX at the faucet farthest from the water inlet, disconnect the main water feed to the system at the Anderson valve, and using an air compressor try to blow out the line from the faucet end (backflow). There will be water from the
PEX tubes shooting out of the water supply end, so rig up an extension hose, water pail, or a lot of rags to cover this. You will probably want some rags/towels at the end where you apply the compressed air, too.

Thanks, Bill. I have begun to consider some form of air pressure.
 

BigHorns

Member
Check the faucet screens for signs of debris.

Also, it sounds like what happens when an accumulator discharges. Is there an accumulator installed? That would indicate general plumbing downstream of the accumulator is ok and the problem is somewhere near the inlet of the system.

I didn't mention the screens, but I have checked the shower and the kitchen sink screens. Clean.

There is no accumulator tank installed (though I've long considered it). I believe that your theory of downstream plumbing is OK and the problem is very early in the system is spot on. When this deterioration in flow began, it affected (and still does) every water outlet in the rig- sinks, shower, toilet, washer- the same way immediately. I guess I'm increasingly convincing myself that any problem has to be in the cold water line right behind the Andersen Valve and before the line begins to split into its various directions. And that's a very short distance. I can't explain a common behavior at all water outlets otherwise.

I'm considering cutting the pex right before the first split and putting a new connection there that I can test with and put back together easily.

But all that said, I still have a problem buying some kind of obstruction due to the fact that as soon as you open any water valve in the rig, water pressure at my gauges outside nearly bottoms out and returns to 55 pounds soon as you close it. If there was an obstruction, pressure on those gauges should remain up at least a little due to the obstruction. That all points to low flow from the park but my neighbors don't complain of the issue. Baffled.
 

Hollandt

Member
I have been fighting the proverbial water flow problem for several months and am finally crying uncle. I do understand the difference in issues of pressure vs. flow rate.


My pressure regulator at the spigot (the good Valterra unit with gauge- not the cheap one) will read over 80 PSI currently before I dial it back to around 50-55. I have another gauge at the connection in the UDC which typically reads 43 PSI (after a simple inline filter). These readings with a closed system, of course.


Turn a faucet on- anywhere, or open the toilet valve, and I get a rush of good pressure/flow for a couple seconds and within, maybe, 10 seconds, I've got a tiny stream.


From the spigot I have: spigot -> Valterra regulator/gauge -> 4-way brass splitter -> inline filter -> hose to UDC. All the 4-way connections are closed except the one in use here. Some example flow rates from testing filling a half gallon bottle:


  • 45 secs to fill the bottle from the kitchen sink faucet
  • 20 secs to fill the bottle straight from the hose otherwise connected to the Andersen Valve in the UDC.
  • 8 secs to fill the bottle through the same hose but with the inline filter removed.
  • 42 secs to fill the bottle from the kitchen sink faucet with the inline filter removed.


I also pulled the Andersen Valve out and filled the bottle directly from its city water port- it overflowed it in nothing flat.


Every indication is that there is an obstruction in my in-house system. But if there was, pressure should remain higher between the spigot and UDC gauges while water is flowing but it does not. Also implied would be a leak in the system. I'm dry as a bone inside, in the belly (I've pulled access panels), and on the ground. And with a leak, system pressure would not return as soon as you close an open valve.


Other notables:
  • This has been an issue in multiple parks with, ironically, unusually high water pressure,
  • I generally use a RV Water Filter Store 3-filter setup with their softener; they are not in the system currently,
  • I have disconnected/examined numerous pex half-inch threaded connectors. I don't have an ounce of corrosion exhibited anywhere. Also removed the screen filter in front of the onboard pump- it is crystal clear,
  • Other resort guests do not have the issue.


And, finally, this whole scenario occurs both on city water and on the onboard pump from the fresh tank. And it has deteriorated to this point only in last couple months. Been in the rig 18 mos.


I'm lost. Any ideas on what I'm missing or misinterpreting?





...Bill

Have you tried a different regulator or no regulator? The regulator although a pressure regulator, regulates by controlling flow. If the mechanism has become clogged or damaged it maybe still regulating pressure when at a low flow rate, but cannot open enough to allow the higher flows required?
 

david-steph2018

Well-known member
I have been fighting the proverbial water flow problem for several months and am finally crying uncle. I do understand the difference in issues of pressure vs. flow rate.

  • I generally use a RV Water Filter Store 3-filter setup with their softener; they are not in the system currently
...Bill

We have the same setup (3 filter and a FLOPUR softener). In 1 park in Lake Havasu we lost water flow from the kitchen sink, and had low pressure in the other areas. When we got to our next campground I took the kitchen faucet apart and turned on the water. After a few seconds I had a lot of black pieces come out. I think it was the resin in the water softener that plugged the kitchen. Just removing the screen at the end did not help us, I had to take the end off the hose to have a clear line.
My thoughts since I did not store the water softener upright during travel, some of the resin made had got into the discharge area and made it's way into the RV.
 

TedS

Well-known member
The check valve in the city water inlet may be misbehaving. If so, it would be a restriction giving the pressure reading differences during water flow.

The air bubble in the water heater would act as a small accumulator.
 

centerline

Well-known member
it seems a lot of people arent reading what you're writing.... as i understand it, it happens on city water and from the onboard pump.... which means it has nothing to do with the water regulator, and not an air bubble somewhere either.. or an accumulator issue...

I have the same problem in my bighorn unit...

a plugged line, with say a pin hole passage will allow the "standing" pressure to build on either side of the obstruction.... but when the spigot is opened, the pressure bleeds off, and even though the water pump or city water flow and pressure are still the same, the "flow" thru the restriction causes very little water to trickle out of the spigot...

so yes, there is an obstruction somewhere...

i hope if you find the issue, you will do a follow up and let us know what it was you found....

what i know is, and am disappointed that some "educated" engineer in the design department thought would be acceptable is, the pex line in the trailers is 1/2" ID for flow... but the plastic connector fittings an elbows only have a 5/16" hole thru them.... and with the number of connections in the line, thats a huge restriction in itself... if they used the brass fittings, it would cost another $50 collectively, to outfit the entire system with a fitting with a 3/8 hole thru it... its only 1/16" bigger, but this is a substantial difference when one considers the dynamics of hydraulic flows and forces...

this is not enough to cause the issues that we are having, but it does effect the shower pressure.... we can restrict the flow, IF THERE IS PRESSURE enough to spray the water, which for a good shower, one can either have good pressure with a small amount of water, or a LOT of water with a small amount of pressure... and we all know which is the best in an RV... why the engineers cant figure this simple stuff out, and design it this way is beyond my comprehension...

please let us know what you find, and if i run across the problem, i will do the same..
 

TedS

Well-known member
Look for a pinched line somewhere after the common pump/city water and the split to the water heater. This would be plumbing common to all downstream fixtures.

Changing the inside diameter of the plumbing makes a large difference in flow area. The area changes by the square of the diameter change. That 1/16 make a 40% change in flow area.
 

centerline

Well-known member
Look for a pinched line somewhere after the common pump/city water and the split to the water heater. This would be plumbing common to all downstream fixtures.

Changing the inside diameter of the plumbing makes a large difference in flow area. The area changes by the square of the diameter change. That 1/16 make a 40% change in flow area.


"Changing the inside diameter of the plumbing makes a large difference in flow area. The area changes by the square of the diameter change. That 1/16 make a 40% change in flow area".

exactly.... I dont know anyone who would think its ok on a system that has limited pressure. EXCEPT an RV designer/engineer....
 

wdk450

Well-known member
"Changing the inside diameter of the plumbing makes a large difference in flow area. The area changes by the square of the diameter change. That 1/16 make a 40% change in flow area".

exactly.... I dont know anyone who would think its ok on a system that has limited pressure. EXCEPT an RV designer/engineer....

That smaller diameter at the fittings/connectors would be a prime place for any debris in the lines to wedge.
 

david-steph2018

Well-known member
We have the same setup (3 filter and a FLOPUR softener). In 1 park in Lake Havasu we lost water flow from the kitchen sink, and had low pressure in the other areas. When we got to our next campground I took the kitchen faucet apart and turned on the water. After a few seconds I had a lot of black pieces come out. I think it was the resin in the water softener that plugged the kitchen. Just removing the screen at the end did not help us, I had to take the end off the hose to have a clear line.
My thoughts since I did not store the water softener upright during travel, some of the resin made had got into the discharge area and made it's way into the RV.

UPDATE:
Left Gallup, NM had good water pressure no issues. Pulled into Santa Fe, NM later that day and did NOT have water to kitchen area. I had to remove the water pressure regulator because the pressure here is low, then we had water in the kitchen sink.
 

centerline

Well-known member
UPDATE:
Left Gallup, NM had good water pressure no issues. Pulled into Santa Fe, NM later that day and did NOT have water to kitchen area. I had to remove the water pressure regulator because the pressure here is low, then we had water in the kitchen sink.

the water pressure regulator?... are you referring to the city water pressure regulator, or dind you find one somewhere else in the system that the pump also runs thru?...
 

RickL

Well-known member
UPDATE:
Left Gallup, NM had good water pressure no issues. Pulled into Santa Fe, NM later that day and did NOT have water to kitchen area. I had to remove the water pressure regulator because the pressure here is low, then we had water in the kitchen sink.

I’m assuming your hook up is EXACTLY the same between the two parks. Nothing added or removed. How was the pressure to the other faucets and toilet between parks? In that the flow comes trough the water pump for both city and tank, if it’s like my Oshkosh I can unscrew the connections on both sides of the pump (I apologize if you mentioned doing this already). I would see how the flow is to the pump and then thru the pump. There’s a check valve that could be an issue. Just an uneducated guess.

Sometimes as we get deeper into the diagnosis we miss the easy things. I’d back track and follow the flow from the beginning to eliminate possible issues.
 

chaplady

Well-known member
Had issue with reduced water pressure n flow found one of the inline hose screens clogged up changed out was fine afterwards
 

david-steph2018

Well-known member
I’m assuming your hook up is EXACTLY the same between the two parks. Nothing added or removed. How was the pressure to the other faucets and toilet between parks? In that the flow comes trough the water pump for both city and tank, if it’s like my Oshkosh I can unscrew the connections on both sides of the pump (I apologize if you mentioned doing this already). I would see how the flow is to the pump and then thru the pump. There’s a check valve that could be an issue. Just an uneducated guess.

Sometimes as we get deeper into the diagnosis we miss the easy things. I’d back track and follow the flow from the beginning to eliminate possible issues.

Hooked up the same. The water flow in the other areas was very low. We do not have the same faucet as what was originally installed at the factory. Wife wanted a different style, and that was an upgrade to one listed as "commercial grade" from Lowes. We have had low water pressure in a couple of parks and the kitchen faucet does not work, but once I remove the pressure regulator it functions, and pressure is better in the other areas.
 

BigHorns

Member
I would suggest that you disconnect the cold water PEX at the faucet farthest from the water inlet, disconnect the main water feed to the system at the Anderson valve, and using an air compressor try to blow out the line from the faucet end (backflow). There will be water from the
PEX tubes shooting out of the water supply end, so rig up an extension hose, water pail, or a lot of rags to cover this. You will probably want some rags/towels at the end where you apply the compressed air, too.

This is not something I had previously done so finally got a chance yesterday. Disconnected cold PEX at kitchen sink and at Andersen Valve city water output port. Blew out with up to 40 PSI from kitchen end. Poured the water it blew out through a fine strainer and saw nothing but clean, clear water.

I've attached here a diagram that helps put this whole head-scratcher into perspective.
 

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