Saturday, December 2, 2023


Ask Dave: Is the white “gunk” in RV’s water hose causing low water pressure?

Dear Dave,
I have always been mindful of water pressure and would never hook up without a water restrictor at 40 psi. I was in a campground in the Arizona desert for 5 months. A strong storm caused an abrupt shutoff of electricity for 3 days. A few days later, after the electric returned, my water pressure in the rig dropped, but it did register at 40 psi at the post. The pressure was too low for showering, the toilet produced very minimal water for flushing, and the kitchen sink water pressure was minimal.

I checked the water hose connection on the outside wall and attempted to remove it but noticed that the connection was corroded with a white gel that hardened on the hose and wall valve. I turned off the water and had great difficulty unscrewing the hose from the wall. This occurred quickly. It was loaded with white creamy stuff that solidified on the hose connections. Never saw anything like this nor have I ever had water pressure issues. My connections were always clean.

Campground did not have a filtering system

It appears that the water in that area is loaded with highly corrosive goop and, obviously, that campground did not have a filtering system. Shame on them. I left that campground and am now in another spot just up the road. That campground told me they have the pressure set for 40 psi. But I still use the psi restrictor and have new connections. However, my water pressure is still not normal for showering, toilet use or kitchen use. I do not have that white crud after the connections were changed, but the pressure is still not normal in my rig.

I’m pushing it with the pressure up to 55-60 that allows me to shower. I called an RV mechanic, but he “soaked” me changing the water pump that I agreed to get. But that’s not the answer. So, the pump gives me good pressure, but it still did not resolve the normal pressure from the water source on the post.

I now have it at 60, which I do not feel comfortable with. I want to try to pour in and soak the house pipes with baking soda and vinegar. What is your take? Where do I put it into the system? I am afraid there may be an expensive problem. —Sharon, 2014 Keystone Laredo

Dear Sharon,
What you most likely experienced was calcium and lime that is common in hard water typically from well water at campgrounds. Certain parts of the country have very clear ground water while others have tremendous amounts of calcium, lime, and even rust. Most campgrounds use a well with pump. Very few condition the water like a city municipal water treatment plant would. So you run the risk of clogging up your water pipes, fittings, and faucets.

I recommend using a water filter

I highly recommend a filter at the hose along with your pressure regulator. There are several in-line versions. I like the residential-style blue Omni brand you can get at any home improvement store or hardware store. This allows me to choose the type of filter I need and replace just the filter at about $4, instead of the entire filter which can run up to $25 or more.

So, let’s take a look at what might be causing restriction in the water flow. The first thing I would look at is your city water connection. This has a spring loaded “check valve” that keeps water from flowing out when you use your onboard water pump. Since you found “goop” in the hose, I would disconnect this and clean it out or replace it. There should be just three screws holding it into the sidewall. However, it is most likely sealed with silicone or similar product and might be hard to pull out. Use a razor knife to cut the sealant and it should come off.

Since the shower pressure is good using the water pump, that indicates the plumbing after the pump is most likely clear. You did not indicate if any other faucets or the toilet have low pressure, so I assume they are fine. That would lead me to believe the water line going from the city connection bypassing the pump is most likely clogged. Here is a diagram of a Winnebago model showing how it bypasses and supplies pressurized water to the rest of the coach like the water pump would.

You might be able to use a flexible “fish” wire by taking off the city connection and trying to shove it in through the 1/2-inch pipe. They sell very small versions of these at home improvement stores and discount tool locations. Otherwise you will need to replace the hose, if you can access it.

 You might also enjoy this from Dave 

Is my RV’s water pressure low because the regulator is plugged up?

Dear Dave,
I’ve used my brass adjustable water pressure regulator for several years to ensure <55 psi through the water lines in our ‘07 Tiffin Allegro coach. Lately, even after I disconnect the water source, the gauge on the meter has been sticking at whatever pressure it had been registering – but by the time I hook up again, it’s fallen back to 0. We volunteer for national and state parks around the West, frequently for 3-6 months at a time. As you can imagine, water quality varies considerably. The last two places I’ve hooked up, the water flow inside the coach seems to be lower than the gauge reading would indicate. Do water pressure gauges clog up with lime, calcium, etc? If so, can it be cleaned? Or is buying a new one ($50+/-) the only option? —Tim

Read Dave’s answer.

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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Dave Solberg
Dave Solberg
Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club. He has been in the RV Industry since 1983 and conducts over 15 seminars at RV shows throughout the country.



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Joe (@guest_208348)
1 year ago

This does not make sense to me. If the hose and faucet is plugged up why not the rest of the campgrounds water piping, pump, and associated equipment to maintain pressure. A park on a well or on a municipal water system will utilities components such as pressure regulators, valves, level switches, pressure switches, gauges, and such that would also get clogged causing many issues throughout the campground or the whole municipality.

KellyR (@guest_208358)
1 year ago
Reply to  Joe

My stix n bricks is on a well, HARD water, lime, calcium, iron. The lime and calcium can build up on the sides of the water line and sort of does not cause a water flow problem, but does clog valves and faucet screens occasionally. To me, the power going out was the clue. If the power goes out and on a well, when the power comes on and the well pump kicks in, it will be more of a surge, rather than normal flow and will break that white junk from the walls of the pipe or out of upstream valves and come out as gunk. It sound to me like a gob of gunk got stuck SOMEWHERE along the line. Finding the SOMEWHERE is the problem. If you can take the line off before your RV water pump and flush backwards, that may work. Yep, it will be WORK.

Bob (@guest_208298)
1 year ago

Nothing was mentioned about the screen on the city water inlet. If debris came though after the water was restored, more than likely something is clogging the screen.

Gary (@guest_208327)
1 year ago
Reply to  Bob

Also the screens on the faucets.

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