Water pump motor sound

[Jeff in Ferndale Wa]

While prepping the trailer for an upcoming week long trip, it took a minute to get the system up to pressure after I flushed the lines a bit.
Once it stopped pumping I noticed the motor humming slightly. It wasn't hot.
I don't recall it doing this before. Is it possible that it has always done that and I am just now noticing? I will watch it over the next week and see what happens.

 

[SpencerPJ]

Hard telling, you know your TT best. They make a basic rebuild kit (maybe it's not sealing perfectly). If you belong to Amazon Prime, you might buy a kit, or heck even a spare pump. The beauty is, return it unused if you don't need it, have it if you do.

 

[Henry J Fate]

without knowing your specific pump and installation, generally when the pump stops pumping, motor power should also cease.

double check to see if it is a motor hum you are experiencing and not another component close by or in the plumbing circuit.

it also could have been a temporary issue triggered by a fresh start up after a flush. an abundance of air could possible create a disturbance within the plumbing.

 

[OldWEB]

Once it stopped pumping I noticed the motor humming slightly. It wasn't hot.

DC does not hum, unless the motor is running. Or you do not have your batteries connected and the Converter is supplying the unfiltered DC.

 

[Mark_K5LXP]

I noticed the motor humming slightly.

So teach it the words. [rimshot] Maybe with air in the system there's a check valve that's leaking. Does the sound diminish as pressure changes or does it come and go with the pump switch?

Mark B.
Albuquerque, NM

 

[Jeff in Ferndale Wa]

Thanks for the replies guys.

Batteries are connected and the trailer has been on shore power the whole time it has been parked.

The pump is located under the vanity in the bathroom,and I don't think there are any other components nearby, but will look closer. It could very well be a temp issue caused by the startup.

I don't know the words....

We are leaving Sunday for 5 days and will watch and listen closely and see what I can figure out.
At least I can be reasonably certain it's not going to heat up and catch fire.

 

[Kirk]

At least I can be reasonably certain it's not going to heat up and catch fire.

Are you certain that the sound is from the pump and not something else that seems to be from that area? If it is the pump you should be able to feel some vibration of the motor as the pump is physically mounted to the motor. I have a suspicion that the hum is something else. The PEX water lines are well known for carrying vibrations through RVs.

 

[Jeff in Ferndale Wa]

Are you certain that the sound is from the pump and not something else that seems to be from that area? If it is the pump you should be able to feel some vibration of the motor as the pump is physically mounted to the motor. I have a suspicion that the hum is something else. The PEX water lines are well known for carrying vibrations through RVs.

Not certain at all. I don't think there is anything else nearby, but I need to look closer to be sure.

 

[OldWEB]

Maybe once it pressurized, the check valve was not seated properly and allowed seepage back to the tank, causing a 'vibration' or hum. Had the pump restarted by chance?

 

[JudyJB]

I have had a lot of water pump problems over the years. One trick is to turn a faucet on and off a couple of times to get rid of trapped air. Might even want to do that with two faucets, one in kitchen and one in bathroom. Mine hummed a bit the other day. Mine also occasionally runs really loud--thumping, etc. I do the same thing or at least turn it off for a while and it usually fixes itself.

In almost 11 years, I have had 6-7 pumps. I even talked to manufacturer and they think there is a tiny air leak somewhere, but Fleetwood factory tried twice and cannot find it.

 

[jackiemac]

Ours does that when air still present and usually at start of trip or after filling tank.

 

[Rene T]

Just a little tip. Before connecting the hose to the rv, open the spigot and fill the hose with water before connecting it to the rv. This will eliminate 99% of the air in the hose

 

[8Muddypaws]

"Just a little tip. Before connecting the hose to the rv, open the spigot and fill the hose with water before connecting it to the rv. This will eliminate 99% of the air in the hose."

And bugs!

 

[Jeff in Ferndale Wa]

Just a little tip. Before connecting the hose to the rv, open the spigot and fill the hose with water before connecting it to the rv. This will eliminate 99% of the air in the hose

I don't think that will make a difference when running from the water tank.

 

[Gary RV_Wizard]

If it is a variable speed pump, the hum could mean it is running at very low speed. That would suggest a leak somewhere, including the possibility that water is trickling back to the tank via the city-tank fill valve.
If not a variable speed model, it should be either full-on or off. No hum either way

 

[DutchmenSport]

Simple solution to determine if the sound is truly the pump or not. Turn the pump off at the switch inside the coach. If the sound goes away, it was the pump. If it stays on, it's not the pump.

Now turn the switch back on. Do you hear the sound again?

 

[Jeff in Ferndale Wa]

Simple solution to determine if the sound is truly the pump or not. Turn the pump off at the switch inside the coach. If the sound goes away, it was the pump. If it stays on, it's not the pump.

Now turn the switch back on. Do you hear the sound again?

Yes,it stops when you turn off the switch.

 

[Rene T]

I don't think that will make a difference when running from the water tank.

I never indicated running from the tank. I said before connecting the hose to the rv. It was just a tip to help others.

 

[Jeff in Ferndale Wa]

I never indicated running from the tank. I said before connecting the hose to the rv. It was just a tip to help others.

no, but you made the comment in a thread that is discussing running the pump from the fresh water tank, not the city water supply

 

[DutchmenSport]

From everything I've read on this thread and from your description of the problem, I think the pump is not pressurizing, thus it keep running.

Now, what is keeping it from pressurizing.

The first possibility is, the pump itself is leaking air. I had this happen to one of my previous trailer pumps. It turned out the screws holding on the pump wheel had backed out. There was actually only 1 screw holding the cover in place. Unfortunately for me, 2 of the screws were completely missing. I had to buy a new pump.

Second possibility: The check valve that stops the water from returning back to the fresh water tank is not working. The pump is literally cycling water from the fresh water tank and then right back into the tank. The system never pressurizes to turn the pump off.

Third possibility: The pump itself may have gone bad. Simply, it's the pump itself, the pressure regulator to turn it off, is not working, so the pump just keep spinning.

Fourth possibility: You have air in the water line somewhere not allowing the system to pressurize. However, if there are no leaks and everything is working correct, eventually even those air pockets will pressurize and the pump will eventually shut off. Think of how pressure tanks work, and that air pocket in the top of the water heater? This is not a likely cause, but stranger things have happened.

Fifth possibility: You have an actual water leak. But if that was the case, you'd have something flooded somewhere and you'd have water running across your floor and dripping from under the camper somewhere. If you have no water spewing anywhere, then is probably not the cause.

My best guess is, the water pump itself need replaced. For some reason, even if the pressure regulator is working correctly, it's still getting power. It's not shutting off the power completely between cycles. If it's "humming" that means eventually the motor will burn itself out. You can go to any RV dealership and get a new one. They are pretty easy to swap out. If it were mine, that's what I'd probably do. (only because I did have a water pump problem once before that did something very similar.)

Good luck!