Plumbing- where is the "external water supply source valve"?

Doug Allen

Advanced Member
Joined
Jul 10, 2017
Messages
59
Location
Upstate South Carolina
Two weeks ago I tried to use the 30 gal fresh water tank and the pump without success. The fresh water tank release valve tubing below the tank had a leak which I fixed today with new tubing and a shut-off cap. I hoped that was the problem.
Not so! I filled the tank 2/3rds full according to the monitor. When I engage the pump, I hear it, but no water is pumped to the faucets. I have let it run for about a minute several times. I'm afraid to let it run longer without pumping water.

I just reread the 1999 original manual again and see that there is a "external water supply valve", but it doesn't show where it is. It must be near the pump? If so, I can't find it?

Two weeks ago some of you also said I must turn a valve, and I looked for it around where the tubing enters and exits the pump, but couldn't find a valve. Just spent another 30 minutes looking for and feeling for the valve.

I can see the pump and the tubing and 90 degree joint connectors. Some of it is blocked by the 12V fuse panel, but I can feel the tubing and joint connectors behind it. Some tubing is behind the hot water tank, and I can't see or feel there.

I thought possibly I had found the valves when I looked in the cabinet below the sink, but no, those valves are for cold and hot water to the bathroom.

There's nothing like those valves near the pump. Is the valve I'm looking for possibly on the exterior or under the rig?

What does the external water supply valve look like that I am searching for? Is it like the valves I found under the sink? Would it be on the input or output of the pump. Is the filter on on the input or output of the pump? You guys have been great. Sure hope someone can help with this!
 
I don't know of ANY "external water supply valve" Doug. I wonder if this is in reference to the "winterizing valves" that are normally near the inlet side of the pump?

The intake valve there has a length of plastic tubing connected to it that you stick into a jug of antifreeze. It needs to be closed or you will be sucking air.

There are also 2 more valves part of this setup that are on the opposite ends of a vertical pipe (at "Tees"). On mine, one is in front and one is behind the pipe. These have to be turned horizontally to allow water from the fresh water tank and the hot water tank to be pumped.

Now, in my trailer, if the pipes are empty, it takes some time to pressurize them. I actually open the sink tap slightly to allow the air in the pipe to be forces out. I think I have to run the pump at least two minutes (maybe even longer) to fill the pipes.

If you're not pumping water out on the ground, I suspect your winterizing valves could be set wrongly. Or, your pump COULD be shot. In any case, once you've found your valves, just let the pump run for a longish while. If it's broken, you won't hurt it further.

Have the trailer hooked up to shore power while you do this to keep the battery charged. The pump actually pulls a few Amps.

- Jack
 
Thanks Jack,
Very frustrating. It's one of those days I worked hard and accomplished nothing! I'm now thinking that the "external supply supply source valve" is merely the the "city water" faucet and that there is no other valve on the interior or the exterior of the coach to switch between city water and pumped water. Is that possible?

I've spent two more hours looking for it, drawing a diagram of what I can see, and also watched 2 hours worth of Shur-flo pump videos, but no joy.

I've determined from the videos and by removing the "strainer" that is on the vacuum side of the pump and watching videos that the tubing that enters the strainer and pump is connected to the water tank with a few feet of tubing. No valves.

Another tube comes through the floor from that tank and has no cap on it. I guess it provides air so that a vacuum doesn't build up in the tank?

The output of the pump goes along the front wall of the rig and behind the hot water tank. I disconnected it and water poured out so I quickly reconnected it again. There are no valves between the output of the pump and where it becomes invisible behind the hot water tank on the driver's side of the rig close to where both the city water supply input and fresh water tank inlet are located.

on the rear side of the hot water tank, the side closest to the faucets and toilet, a tube emerges and through a tee, one side goes to the input of the hot water tank and the other toward the rear of the rig where those faucets and toilet are located. The other side of the tee goes to the input of the hot water tank. The output of the hot water tank and goes behind the refrigerator to the rear of the rig to supply hot water and parallels the cold water tubing.

There are NO valves on any of the described tubing. A sensible place for a valve to switch between the city water and the pumped water would be behind the hot water tank, and I would have to remove the tank to see if there is a valve there. Surely it wouldn't be that inaccessible! The valve might also be on the exterior near the fresh water fill or the city water supply line or close to the hot water heater open drain valve and the pressure relief valve back of the cover of the hot water heater cover. No indication of any valves in those places.

I guess it's possible that someone modified the plumbing, deciding not to use the pump, and the valve was removed? IF ONLY SOMEONE WITH A 1999 VINTAGE TOWLITE WOULD TELL ME HOW THEY SWITCH BETWEEN CITY AND PUMPED WATER I COULD GET SOME CLOSURE! Sorry to shout, but I feel like I've had a wasted day.
 
Doug - I'm afraid I can't help you. In my trailer, there's NO valve to switch between city and tanked water. You simply don't use the pump if connected to a city water supply. In addition to the three winterizing valves I talked about, I have two drain valves (one each) in the cold water and hot water lines to to faucets.

My cold water tank has an overflow tube (opening is beside the inlet) that allows air to enter the tank as water leave it.

I would expect your water pump to be located fairly near the hot and cold water supply tanks. But, I haven't really traced my water lines like you have. Thinking about it, I'd have to say the pump must supply cold water to the hot water tank inlet, which in turn forces hot water out to the faucets.

Maybe we'll get lucky and someone with a trailer more like yours will chime in. I hope so, because I'm at a loss.

- Jack
 
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Doug (& Jack) - I'm afraid I can't help you. In my trailer, there's NO valve to switch between city and tanked water. You simply don't use the pump if connected to a city water supply.

Hopefully, I won't have this problem with my "new" 2000!

I presume that it is set up the same as my 1976, in that, there is a Check Valve between the Trailer lines and the City Supply and Fresh Water Tank. IF you're hooked up to City Water it bypasses the pump and the Fresh Water Tank.
 
Jack, I really appreciate your quick replies and your experience. When you say "there's NO valve to switch between city and tanked water", it makes me think my pump may not be working. When I remove the water tank input tube, I feel no suction using my thumb to close the input opening.

I wonder if I should feel suction if the output of the pump were blocked by a closed valve or something else. One of the videos I watched showed how to repair a Shur-flo pump. The pump is a Shurflo 1998 model 2088.

I'm reluctant to try and repair or replace the Shur-flo pump until I hear from someone who is using one in a similar rig to mine and describes what if anything they have to do when switching between city water and pumped water besides removing the city water hose.

Hmm, you say, "My cold water tank has an overflow tube (opening is beside the inlet) that allows air to enter the tank as water leave it." So does mine, so what is that uncapped tube coming from the water tank if not a air tube? Maybe it's "The intake valve which has a length of plastic tubing connected to it that you stick into a jug of antifreeze. It needs to be closed or you will be sucking air. " When I close it with a thumb, there still no water pumping or suction on that tube or at the pump water inlet.

I have a valves for the 30 gal fresh water tank underneath the rig and for the smaller hot water tank, inside the hot water tank enclosure. The only other valve are underneath the sink to turn off and on cold and hot water to the bathroom.

I guess I'll drain the fresh water tank and give up the idea of boondocking until I hear from someone who has the same pump setup as I do and can suggest what I do next.

Having been a ham since 1955, Extra Class, and built some of my own my own radio equipment over the years, I feel pretty competent with electrical circuits, but not competent at all with pumps and plumbing!
 
Yup! Pumps and plumbing is a whole different animal!

You may not feel suction if the pump is not a "positive displacement" pump. Such a pump will not create enough of a vacuum to feel or even to pull liquid "up" to its inlet if it is filled with air. But, if water is introduced to the inlet side (from the tank), then it will pass that water on through and will continue to do so as long as the line supplying the water is filled. Once it empties, the pump cavitates and it stops supplying pressure downstream.

I'm pretty sure your cold water supply is uphill from the pump, so the pump should be seeing water in that line.

You mentioned earlier that you could disconnect a line that was downstream from the pump, and that water came out. That should slow to a trickle or stop once any pressure is lost. But, if you started the pump, it should flow strongly if the pump is working.

Can you disconnect that fitting and direct the output to a big bucket or to outside to check?

In some ways, water IS like electricity and the troubleshooting is somewhat the same. Start at the source and see where the interruption occurs as you progress along the circuit.

Edit: I have NO valving under either the bathroom sink or the kitchen sink. Could yours possibly be cutoffs that prevent water from getting to any outlet? (Of course if city water works, that question makes no sense does it?) It's just puzzling to me why you'd have those valves there. There's no need for them in a trailer - in a house, you turn them off if you have a line leak above them to the sinks.

- Jack
 
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Forgive me for not reading all of the previous conversations, but here is what I think. FWIW. The external water supply source valve is the hose bib valve located where your garden hose attaches to the source, (house, campground or whatever supplies the water).

You should not need to do anything to switch from pump water to city water. A check valve will keep the pump water from going out the city water inlet and I believe there is a check valve to keep city water from back feeding the pump.
 
Thanks Thankful,
You confirmed what I have been thinking that I don't have to search for a valve in order to switch from city water to the pump. I may test the pump the way Jack suggested, but more likely I'll drain the water tank and do that later following a a short camping trip to a nearby RV park. If only the rain would stop!
 
I removed my previous suggestions after I took a look at my water system and realized I was wrong in how I thought it was set up. Hopefully no one had a chance to read it!
My apologies to all.
 
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I does take awhile to fill the hot water heater with the pump when everything is dry. Ususally you can get some water out of the faucet while it fills but it is lower pressure and full of air pockets until the tank fills and all the air is out. There are at least 2 drains in the system that could be open, and the pressure relief on the hot water heater could be jacked open by the lever. The Zink rod and plug could be pulled out of the hot water heater as well. If all that checks out I would pull a line off right after the pump and see if it pumps water. If it doesn't then the motor may be running but the pump end may need replaced or rebuilt, the coupler between the pump and motor could be broken or loose as well
 
Bobin,
thanks for help. Bought 8' of tube and a brass fitting to connect to the tank side (that's the side where the strainer is- right?) and connected it to the pump and the other end to a jug of water. Turned on the pump and it was not drawing any water from the jug, but I forgot to turn on the sink faucet so I have to do that again.
A couple days ago when I disconnected the output of the pump water spilled all over and I quickly reconnected it. I guess the water coming out was from the hot water tank which is higher than the pump. I had just previously been connected to city water and had the hot and cold faucets turned on which probably filled up the hot water tank. It's raining again so I'll continue tomorrow.
 
Hersbird,
Thanks for help. The pressure relief on the hot water heater and the zink rod and plug are both closed, and there are no leaks when using city water.
"If all that checks out I would pull a line off right after the pump and see if it pumps water. If it doesn't then the motor may be running but the pump end may need replaced or rebuilt, the couple between the pump and motor could be broken or loose as well"
Doesn't pump water of have any suction, but I'll open sink faucet and try again. I think you identified the problem Hersbird, but I'll try a few more experiments before replacing the pump.
 
You can get rebuild kits for pumps but I think I would replace instead.
 
My 2001 unit had a valve that allowed me to switch from city water to filling my fresh water tank. I just connected the water hose to the city water connection on the outside and opened the valve near my pump to fill the fresh water tank. If I didn't close the valve, the pump would just suck air and not pressurize the system. Thus no water using the water pump until the valve was closed. Hope I made this post clearer than mud. :)

Bob
 
It was clear to me Bob. But, from the previous posts, it doesn't sound like he has that valve - even though it could well be the "external water supply source valve" he originally posted about.

Doug, you're probably tired of this (I would be) but if you can stand it, feel around BEHIND every pipe tee and other joint for a hidden valve. In my trailer, the one behind the piping is not visible and I had to locate it by feel. Maybe, you DO have one and you just haven't run across it.

- Jack
 
Have done this several times Jack and also taken photographs of areas I can't see. The only place I can't see, feel, or photograph is behind the hot water tank, and I would have to remove it to see what's there.

The shut-off valves under the sink go to the shower faucets to shut them off for repair.

This morning I tried the pump again with the kitchen sink faucets open, and I poured water into 3 feet of tubing right up to pump intake, and there was no suction, no movement of the water into the pump. I also did this after draining the hot water tank and again after draining the fresh water tank. No suction and no movement of that 3 feet of water in the tube so, unless someone has another idea, I assume I have a bad pump.
The next question becomes- what replacement pump do you all recommend? Mine is a 1998 ShurFlo 2088-403-144. Don't know what the last 6 digits stand for, but I see the 2088 is still available.
 
If it was me, I'd try this one: Flojet Quiet Quad II Water Pump - Xylem 04406143A - Fresh Water Pumps - Camping World

I'm only suggesting it because it says it's "quiet". But, the reviews on Camping World all seem positive too. You might find it cheaper somewhere else. The ShurFlo Revolution that's offered by Camping World is cheaper and also is supposed to be quiet.

There are many others, though and I honestly don't have any experience with any of them other than the ShurFlo that's in my trailer. It works fine, but the noise when it runs is a bit of a turnoff. I've done what I can to minimize the noise - mounted it on a rubber pad and added short flexible lines to each side of the pump to reduce the vibrations that are transmitted into the trailer.

Doug, I was relatively certain you'd checked the entire length of the piping when I made my last suggestion. I'm glad you didn't get offended by it - it was the only thing I could think of. It really sounds to me like you've correctly determined a pump problem. It seems obvious from your last test that the impeller is not turning. If I were in your shoes, I'd be ordering a new pump too. Dang, I hope that fixes things!

- Jack
 
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Replacing water pump

This is a DIY if you are handy. We had to replace our water pump several years ago as it sounded like a Jack Hammer and didn't want to shut off. The cost is minimal considering how many years it lasts. Don't recall the model. It is a Sureflo a quiet one. Do a search on the internet for the best one.
 
Hi Jack, Sam, et al.
I'm not very handy, but think I can replace the pump. I ordered the Hi-Lo Revolution, Jack, because one of the High-Lo sites recommended it as a replacement for my discontinued 2088 model. Bet the Flojet Quad II would also work. I'll post again after I replace the pump, and I hope my inexperience and your suggestions will be helpful for other newbies.
 

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