Laundry utility pump

[cposty]

Hey all,

This is my first post and I really appreciate any help!

I had a friend that is a plumber install a utility sink and laundry tray pump for the washer in our basement about a month ago. I have noticed that lately water is seeping out around the screws at the top of the pump box. The pump is a Flotec 1/4 HP Submersible Sink Pump System (pump in a box) from Home Depot (insert jokes here).

I have a couple issues that I wouldn't mind getting some feedback on:

First, I was looking at the installation instructions from Flotec's website, and it mentioned that venting should be tied into the existing vent to the sewer. My friend did not do so, rather, he put an ABS in-line vent on the top of the vent pipe. Is this a good alternative?

Second, regarding the leaking water from around the screws at the top of the pump box..is that a float adjustment issue?

If any recommendations for a different kind of pump are out there, please let me know. He is coming by this Thursday to take it apart and look inside to see if there is any obstructions.

Thanks!

 

[jwwing]

First, that type of vent should work ok because the system should have an inline valve that prevents backflow of the air into the room, but allows air to flow into the box

Second, the unit should not leak out the top. Such a leak suggests that the check valve is not functioning or that one was not installed, and also that the pump is not running. The water would flow back into the box after being pumped out and if it does, the pump would keep cycling trying to pump it out. If it gets to the top like that, it means something has failed and the pump isn't running. The float could be stuck as well, not an adjustment per se. There should not be enough pressure in the box to cause a leak out the top.

 

[johnjh2o]

What he used is a AAV. They allow air into the tank but not out like a standard vent would. Without a place for the air in the tank to go when being displaced by the incoming water a pressure builds in the tank not allowing the system to operate properly. The directions have to be followed and the vent must connect to a existing vent or vent to the outside individually.

John

 

[jwwing]

What he used is a AAV. They allow air into the tank but not out like a standard vent would. Without a place for the air in the tank to go when being displaced by the incoming water a pressure builds in the tank not allowing the system to operate properly. The directions have to be followed and the vent must connect to a existing vent or vent to the outside individually.

John

As the water comes in the pressure provided by the washer pump should exceed that necessary to open the output check valve of the pump tank and the water should turn on the sump pump almost immediately. That pressure should not be enough to blow by the screws at the top of the unit and water should never rise to that point anyway.

I agree that the plumber should have installed the standard vent stack up to a location well above where the max rise height of the pumped water, but the system should have worked anyway with the AAV.

If the system is not closed as I have suggested, then there should have been water all over the place. It really sounds like the pump is not turning on and that the washer's pump is doing all of the heavy lifting.

 

[johnjh2o]

The point is that the system should be closed and with out a vent where does the air in the tank go when it is being displaced with water. An AAV doesn't allow the air out. The check valve has nothing to do with it. It's there to prevent the remainder of the pumped water returning to the tank.

John

 

[jwwing]

The point is that the system should be closed and with out a vent where does the air in the tank go when it is being displaced with water. An AAV doesn't allow the air out. The check valve has nothing to do with it. It's there to prevent the remainder of the pumped water returning to the tank.

John

That's right, so the water coming into the tank closes the AAV and pressurizes the tank, pushing the check valve open. My experience is that the ones they use on RVs are not closed tight unless the water or air comes against them to close them and only close if the flow is large enough (that's why there is a little odor associated with them) - so if the water coming into the system is moving relatively slowly, the air will escape out the AAV. Your explanation also does not account for the water on the top (leakage), does it?

I think it is time for the OP to report what his friend found - I agree with your initial assessment about the vent, just don't think it explains what is happening in the OP's system.

 

[johnjh2o]

AAV don't leak, if they did it would fill the home with sewer gas and if they leaked they would never get approved for use in a sanitary system. The reason water is leaking out of the tank is because it's not sealed, which it should be. Because it's not sealed and allowing air to escape is the only reason it's allowing water to enter the tank. As far as your theory that the incoming water creates a pressure in the tank that opens the check valve I'm not sure how this could happen as the pump is sitting in water. It would have to force the water up through the check valve before any air could escape down the drain.

John

 

[jwwing]

LOL, johnjh20, saying that an AAV doesn't leak is like saying ice doesn't melt. But I am only marginally experienced with an AAV that is used in RV applications where the big complaint is 'why do I get this awful odor'. Actually, I think that this could be a good point - that the box isn't sealed so the air escapes - that way the AAV does not have to leak. Unfortunately, if that is the case, you still have not explained how the water got that far - on top of the box. To get water up there, there has to be a serious leak or the sump pump is not turning on, which was my initial take on the problem.

Also, the drain from the utility sink would not drain into the box unless there was some way to get the air to escape. My description of how the AAV works would not allow sewer gas into the box because the only connection between the box and the sewer is the sump pump's exhaust pipe that contains a check valve and a small column of water. Pretty good protection against sewer gas. However, the gas created in the box from fermenting water from the utility sink and the washing machine could provide a small amount of gas, but the gas would slowly dissipate and never be smelled by anyone unless there was a significant amount of it forced out somehow when the first dump from the washer occurs, for example.

Re check valve comment: that is what I suggested was happening originally - once the water got high enough to enter the sewer system, the system's own vent system starts working. Before that, the air in the tank just remains captured in the tank and can't escape. Assuming that the sump pump is not turning on, the system is sealed, and the AAV actually works (and works the way you suggested), the washing machine's pump is pressurizing the system and pushing the water out through the sump pump's check valve so the system appears to be working although it is not. After a few uses, the water in the tank builds up due to small leaks around the screws and when it finally is full, it begins to leak out the screws where all the air leaked out.

All this is guesswork - the OP needs to tell us what his plumber found when he opened the box.

 

[johnjh2o]

I do agree with you that there is also a problem with the float switch. But you a wrong about AAV's. They don't leak like a said they would never be able to get approval for use if they did. And if AAV's would work with the pump why would the manufactures say different? I have seen this tried over and over again and it doesn't work.

John

 

[jwwing]

Yup, and check valves always check, anti siphon valves always release, and toilet bowl flush valves never seep. AAV's are not designed to do what they are being used to do. The AAV is designed to keep a longish drain run from not siphoning a p-trap, not as a vent. When used as a vent, they are notorious for leaking, aren't they? Mostly they allow a little gas to escape - all that is needed is a little something to hold the flapper a little bit open and it will allow air out as well as in.

 

[johnjh2o]

You have taken this thread well beyond the original problem. I can see that no matter what point I make about AAV's you will continue to say they leak. The fact remains that they are a approved device. And if they leaked sewer gas the wouldn't be. As far as I'm concerned there is no point in taking this any further.

John