Water pump always on

[FirstDrop]

Hi,
New to the forum. I have a 2018 Mini Drop 1708. The fresh water pump stays on after the system is filled and does not turn off. There are no leaks in the system. Is there a pressure switch in the water system that controls the pump. If so where is it located.
Thanks.
Steve

 

[ThomB]

Are you saying the pump continues to run even when no tap is open?

 

[FirstDrop]

Yes

 

[creativepart]

There is a pressure switch on the pump that's adjustable with an allen key. You turn it a quarter turn at a time until the pump shuts off. Then as you use the pump you can determine if it needs more or less adjustment to work properly.

I've attached the factory instructions below, but I suggest not taking the screw all the way out unless you really get lost. In your case I'd turn the screw counter clockwise a quarter turn at a time and see if the pump stops. (If after a few turns it doesn't stop, then I'm remembering wrong and you should turn it back to where you started and then go a 1/4 turn at a time clockwise until the pump turns off.)

When the pump turns off you probably are not done. Go test the faucets and especially the shower. You want the pump to come on when you turn the faucet on and turn off when you turn the faucet off. It may take a little playing back and forth with the adjustment screw to get it just right.

PS. I don't mess with the by-pass adjustment shown in the instructions because I always seem to mess things up.

 

[imnprsd]

For those of you who know this problem well, I have a possible solution I need to vet.

QUESTION: Are we talking about a water pump priming problem?

If so, this problem does not seem to be dependent on the type of pump you have.

For example: In my RV I have a water drain line after the pump and when I do have a pump priming problem, which is very rare, I just open the drain ball valve and the pump primes... and then I close the ball valve 3 seconds later. Easy peasy!

So why did Winnebago eliminate the drain line?

My guess is that they started using a less expensive pump, gave you an adjustment screw no one really knows about, and they got rid of the drain line to save time and parts cost. That's what they do.

However, the RV owner on day in the far future, ends up wondering (often it would seem) how to prime their pump? So Winnebago's cost reductions once again cause RVers some frustrations.

INTERESTING STORY

In my case, for years I always considered the drain line after my pump; and the drain ball valve to be useless... until one day my pump just keep running... and I couldn't figure out how to fix it. Just like the OP.

All the faucets were off and there were no water leaks which would prevent water pressure from building up in the lines, sufficient to turn "off" the water pump.

Turns out my ShurFlow water pump had a air gap in it, just like the OP. (Albeit, we have different pumps, I know, but maybe this is the same problem. Is it?

In my case, the solution to priming the pump was this: All I had to do was open that drain-ball-valve and let water out of the drain.

...Then the pump would the pass the air bubble and after that the pump would prime. ...And after 5-10 seconds later water pressure in the line was achieved.

So what I am suggesting is this. If you have problems like the OP is having, is the best method to deal with pump priming problem... Just add a "T-fitting" to the water line coming out of the pump, and install a drain-ball-valve? ...Or is adjusting the pump pressure the right solution?

Note: I don't know if I'm confusing these two issues or not? After all we have different pumps.

However, I have never needed to adjust the screw on my water pump. ...And frankly I don't think my water pump has an adjustment screw, but maybe it does?

So it sounds to me that a better way to fix a pump priming problem is to just add a drain line to line-out of your pump, so you don't have to deal with this adjustment screw business, which I understand is sometimes hard to access. What do you all think? (Granted, I maybe off track so this time I need some commentary.)

I attached a picture of a Flait-it PEX type valve, but that would only work for if your water lines are PEX and you can install a drain line... by cutting a hole in your holding tank floor. ...In my case, I have a 3' flexible line I can snake outside when I need to, which is never. Or you don't even need a drain line if you don't mind water gushing out in your bay; and that too should not be a problem.

 

[njlwa]

Welcome to iRV2.

Do you have a city water/tank valve? if so put it to city water. If left in tank fill it tries to empty and refill the tank.

Help us help you. Please post your make model and year in a signature block. check the control panel for instructions. https://www.winnieowners.com/forums/usercp.php

https://www.winnieowners.com/forums/profile.php?do=editsignature

 

[backtrack2015]

For those of you who know this problem well, I have a possible solution I need to vet.

Just add a "T-fitting" to the water line coming out of the pump, and install a drain-ball-valve?

Would this be dramatically different than just leaving the closest cold water faucet open while trying to prime? Or was your goal here to preserve grey tank space?

Edit: it does sound like the OP's problem is related to the set pressure or to maybe some internal pump leakage (from discharge to suction).

 

[imnprsd]

Frankly, I don't fully understand how an air bubble can (1:100) get trapped in the pump, such that you can't clear it by opening a faucet... hoping that the water back pressure will allow water to backflow into the pump... but it doesn't work this way. So the pump just free-wheels in the air bubble.

Option a) seems involve increasing the pump pressure.

I'm suggesting Option b) maybe more reliable. IDK. I just know I can clear my pump air-gap in 3-5 seconds.

And in my coach, which seems to be missing in newer coaches, is that I have a pump drain line right next to your pump.

And what I see is that my pump will prime.

As for adding a T-Fitting and ball valve, that will take up space. So, maybe I don't understand your question? ...What did you mean by asking: "...was your goal here to preserve grey tank space?

I don't understand what you are asking?

 

[backtrack2015]

My hunch is that leaving a faucet open (the one closest to the pump) would be roughly equivalent to opening a drain valve right at the pump discharge. The only benefit I can see of the drain option is you could route any water that came through during the pump priming process to a bucket. Thus it wouldn’t go down the sink drain into the grey tank. Admittedly that is a very small advantage.

It sounds like the OP’s pump primed just fine and packed the lines with water. It just didn’t shut off afterward. Thus, it seems that either the pump is attempting to achieve too high of pressure (shut off pressure is set too high) or it cannot achieve the proper pressure for some reason (which made me think of internal leakage).

 

[imnprsd]

Backtrack15: I don't think you understand. When you pump gets an air gap the water in the line can't go anywhere when you open the faucet; and the pump can't generate any pressure, because it's freewheeling in an air gap... so it never turns off.

The newer pumps have the option to increase pump pressure.

The older pumps, like mine, have no means of adjusting pump pressure, but we have a drain valve to purge the air gap.

And so far, my opinion, both types of pumps would be better off with a drain line positioned right after the pump.

So we have 2 different pumps, and one guaranteed solution as far as I can tell.

However, it's also true, if you newer RV owners can clear the air-bubble by adjusting the pump screw then there is no reason to do more. ...But what happens if you can't adjust the screw far enough?

A) Buy a new pump.

Install a drain line after the pump.

It's just an option that may prove to be worthwhile. TBD.

 

[backtrack2015]

Backtrack15: I don't think you understand. When you pump gets an air gap the water in the line can't go anywhere when you open the faucet; and the pump can't generate any pressure, because it's freewheeling in an air gap... so it never turns off..

I see what you mean now. I haven’t experienced that. Hopefully I won’t as these little diaphragm pumps seem to do well priming even from a completely dry state.

 

[creativepart]

Do you have a city water/tank valve? if so put it to city water. If left in tank fill it tries to empty and refill the tank.

On a motorhome with both a gravity fresh water fill and a city water inlet diverter fill this would be a good first place to check.