Water Pump Issue

[Gary & Peggy Stevens]

My aux water pump, runs during the day for no apparent reason. Normally if I flush the toilet, run the water in the sink, I hear the pump come on and then about 5 seconds later it shuts off. Now without running any interior water in the bus, I hear the pump kick on.

What would be causing this ?

Gary S.

[merle&louise]

Ice maker?

[Mark3101]

My aux water pump, runs during the day for no apparent reason. Normally if I flush the toilet, run the water in the sink, I hear the pump come on and then about 5 seconds later it shuts off. Now without running any interior water in the bus, I hear the pump kick on.

What would be causing this ?

Gary S.

This is your AUX pump? If so, what about the regular pump? Does it cycle too?

[Jerry Winchester]

Spongebob,

I'm gonna bet the post police are going to move this before the Houston rush hour traffic is over.

But to answer your question, I'm assuming is isn't leaking water onto the ground and I'll bet it's not running it back into one of the waster tanks, so my guess is either the pump is bad (diaphram) or the pressure switch is jacked unless it's internal to the pump. What kind of pump is it?

[JIM CHALOUPKA]

My guess you have an as yet undetectable leak SOMEWHERE in the system, might be internal, might be external.

Your coach is entering the age of the hot water tank replacement and it is possible for the tiniest drip to lower the pressure in the system over time.

This sounds like a tough hunt.

JIM:)

[Jon Wehrenberg]

Gary,

Anyone that does not own your vintage and conversion that gives you advice is generalizing or is offering advice based on their knowledge of their own specific coach.

Recognizing that I do not know your coach, I can only throw out some ideas and you can verify if they are worth anything.

Within all of our water systems we have to have some means of dealing with expansion. Typically that is in the form of an accumulator tank or an expansion tank. If you do have such a device which looks a little like a miniature beer keg it will have a Schrader valve on the top (assuming it sits upright). That valve is used to check pressure and to add air. If you do have one, turn off your pumps, run water until the system has no more pressure, leave the valve open and do a pressure check at that accumulator tank valve. The rule of thumb is to pressurize the accumulator to the pump cut in pressure. If your system is around 40 PSI normal water pressure the pump may kick in around 20 PSI for example. Add air to the tank via the Schrader valve until it reads 20 pounds, close your valve and turn the pumps back on.

Or your system may have a pump with some type of internal expansion tank or accumulator such as later model Headhunter pumps. Those should come on almost simultaneous with opening a faucet. They should not run when you are not drawing water. Check the owner's manual to see if they have any way to add pressure.

But my final thought is if you are not leaking, you do not have an accumulator tank or if you do and it is properly pressurized, then it is likely the check valve which stops water from the pressure side of the pump from passing back through to the water supply side of the pump that is leaking. It is allowing pressure to slowly push water back into the fresh water supply tank, at which point the pump kicks on and repressurizes the system, and water slowly again leaks back into the tank. To verify this make certain you have no leaks. A pump that runs often is eventually going to get something wet if there is a leak. It will be seen as a wet floor, a wet cabinet interior, or water leaking from the bays. Assuming that is not happening, turn off the pump and watch to see if the water pressure starts to drop. If it does and you are certain the coach water system is leak free you can bet a check valve, either in the pump or immediately downstream from the pump is leaking and needs to be repaired or replace.

If you have pumps with an internal check valve sometimes they are not serviceable or the cost to service them is unreasonable. The simple solution is to add a check valve such as one available from a local hardware store or Lowe's into the system. If that is not something you are comfortable doing anyone with some basic tools and the ability to install it pointing in the right direction can do it.

If I am right can we have your dogs? We will take real good care of them and you can pet them at rallies.

[Gary & Peggy Stevens]

Thanks guys for all of the possible solutions. We will be camping this weekend with lots of friends, some of whom know lots more about these issues than I do, so hopefully they will help me look at this issue?
Jon, I can not find an expansion tank for the water system but will delve into looking at your solutions too. My guess, like some of you have said, the pumps are going bad. They are not the powerfull headhunter pumps, but smaller units. I do have two of them, and two seperate switches to turn them on.

So I will spend some time looking over the pumps this weekend.

Jon, it is so nice of you to offer to take my dogs. There have been several times in the past 6 months when I would have gladly taken you up on your offer, BUT for right now I guess we will keep them. Thanks for the offer.

Gary S.

[Jon Wehrenberg]

Gary,

This might be a question for the group, but if a coach is equipped with a pair of Shurflo type pumps will the coach have an expansion or accumulator tank, or is it normal for the pumps to kick on almost simultaneous with with the use of water?

Assuming no leaks, and no accumulator or expansion tank my best guess is the checkvalves, likely internal to the pump are leaking. The problem is, with two pumps you have a 50/50 chance of guessing which one correctly. Just put a new check valve in the system immediately upstream from the pumps.

When you get mad at the dogs Gary give me a call. We'll take them.

[Jerry Winchester]

It probably won't work until after POG X when he takes the Country Coach sticker off, so I'd hold off working on it. Just tell Peg to shower at the RV park bathroom until then.

[charlesebrownjr]

Jon, while reading some of your responses, I am wondering about the accumulator tank I use to have but was removed when I got my SurFlo Extreme pump installed. (Directions said to remove any accumulator tank from the system) All works very well, about 55 to 60psi but what about expansion in my system. What are your thoughts?
Thanks

[truk4u]

I have two Shurflo's hooked in tandem, one is the older smaller model and the other is the newer 5.7 and I have an accumulator tank. My ex CC, now Jamies, had two small Shurflo's and also an accumulator tank.

[Jon Wehrenberg]

Jon, while reading some of your responses, I am wondering about the accumulator tank I use to have but was removed when I got my SurFlo Extreme pump installed. (Directions said to remove any accumulator tank from the system) All works very well, about 55 to 60psi but what about expansion in my system. What are your thoughts?
Thanks

I am not familiar with all the systems out there, or the various pump manufacturers, or how they handle expansion. I do know that if there is no "head" of air pressure the system functions more like a hydraulic system in that as soon as water is drawn the system pressure goes from 55 to 0 almost instantly. Obviously a switch senses that and a pump responds, but most systems I have seen either have an external accumulator or there is one that is internal to the pump. I think of Headhunter Pumps when I say that.

Without an accumulator tank I don't know how the system modulates the pulses from the pump, or if the system is set up to handle the flow requirements of some toilets which need a constant pressure, high flow.

We had this discussion previously regarding HW heaters. Unless the HW heater is designed so it never loses an air cushion atop the contents of the HW tank (pressure HW tanks) the expansion of HW with no cushion will eventually cause the tank to expand and ultimately fail. Within every system except those with instant on HW tanks some means of handling expansion due to heating of the water must be considered.

But in Gary's case, he describes his pumps kicking on when no water is being drawn. Assuming he has no leak it is most probable his check valve(s) are leaking water back into the holding tank and that can be exacerbated by an accumulator tank with no pressure or the lack of an accumulator tank.

[gmcbuffalo]

Gary if you have been in any freezing weather you may have small crack in one of the water lines that is leaking into the coach. So look around for wet areas. Otherwise I agree with Jon that it may be the pumps internal check valve. I have had both issues on a hunting trailer I have. On my bus I have two pumps in parallel and had to adjust the pressure switches on them so they were equal. Until I did this one would run longer that the other after turning the water off and it would turn on sooner than the other. I found the one that was running longer by pulling the wires off each pump during this running issue with no water flow.
Greg

[Gary & Peggy Stevens]

Thanks guys, for all the answers and possibilities.

I am hoping JDUB's answer is the correct one. TOO FUNNY !!!! But worth the cost to help a charity, right JDUB ?

Gary S.

[jimblu]

The Shurflo 5.7 has the pressure switch and check valve in the pump. A check valve after it won't solve the problem if the pump is bad. It is a variable speed pump that doesn't pulse as much. I had two replaced on warranty and switched away from it. Maybe they are better now. If you can shut off the water after the pump and it still cycles the pump is bad. They don't tolerate dirt, they need a pre filter.