Cottage jet pump / pressure tank problem?

[Derek_pied]

I was up at the cottage yesterday to check on it after the winter and decided to try to get the lake water going. The system has a foot valve in the lake, an injector at the shore and a pump & pressure tank halfway up the hill to the cottage.

Every spring I seem to have some sort of little problem with it. This year I inspected and then put it all together, primed the pump (takes about 2 buckets worth of water) and fire it up. It built up to 10 PSI then dropped to 0. It seemed like the pump lost it's prime or something. There was still pressure in the tank. I had to drain the pressure from the tank by opening the hose bib on the output side of the tank, primed it again with a bit of water and turned it on. same thing happened and I did it one more time after that. Then I started looking at other things.

The water enters the pressure tank from the pump on top, and the air valve for the tank is near the bottom. When I took the cap off I could hear some hissing and I could feel a bit of pressure when I covered it with my finger. So that's probably not supposed to happen and needs attention.

What I wanted to know is if these 2 things are related (pressure loss/ prime loss 0-10PSI, and the pressure tank issue)? Obviously the pressure tank needs attention or replacing but since the cottage it 2 hours and a boat ride away I can't hop over to a hardware store to get this and that and the other thing so I want to be armed with anything I might need the next time I go up.

Pressure gauge and pressure switch are 2 years old. I have no idea how old the pump and tank are. They came with the cottage and the way I put it together and operate it are as explained to me when we bought the cottage 4 years ago. The cottage itself is quite a bit higher than the water level which I assume is why the system has the injector.

I would really appreciate any help or suggestions to fix this.

is there an easier system to operate that I should consider that can pump water up a good height?

 

[Reach4]

A submersible pump in a 4 inch pvc pipe in the lake could pump water without needing priming. A 1/2 HP 10 gpm 4 inch pump should give more water volume and pressure than you need.

Power this through a GFCI, and use a pressure switch at the pressure tank to turn the power on and off.

What I wanted to know is if these 2 things are related (pressure loss/ prime loss 0-10PSI, and the pressure tank issue)?

I think pressure tank problem, not related. You may only need a new Schrader valve core, and adjust the air precharge. The precharge for a jet pump is usually about 4 or 5 psi below the cut-in pressure, and for a submersible 2 below. EDIT: I had thought you were referring to the Schrader valve used for air precharge. That may not be the case.

Pressure loss and prime loss could be explained by a leaky foot valve I think. I am not a pro.

 

[Sponsor]

 

[LLigetfa]

There was still pressure in the tank. I had to drain the pressure from the tank by opening the hose bib on the output side of the tank, primed it again with a bit of water and turned it on.

You didn't say what came out when you opened the drain, air or water. If water, then so long as there is not a check valve after the pump, that water should flow back to the pump to re-prime it if you bled the air. It is not best practice to have a check valve between a jet pump and the tank.

A jet pump uses pressure to make more pressure so long as the jet orifice is not plugged.

 

[Derek_pied]

You didn't say what came out when you opened the drain, air or water. If water, then so long as there is not a check valve after the pump, that water should flow back to the pump to re-prime it if you bled the air. It is not best practice to have a check valve between a jet pump and the tank.

A jet pump uses pressure to make more pressure so long as the jet orifice is not plugged.

Water comes out of the drain at a rate higher than what gravity would do so it is pressurized to some extent even though the gauge is showing 0 PSI. There is no check valve between the pump and the tank and what you say makes total sense re: the prime. The prime is only lost after I've drained the tank through the drain.

When I remove the prime plug before releasing the pressure via the drain there is lots of pressure there too, but the line from the pump to the tank is semi-clear and I can see the water flowing through to the tank but when it hits 10 PSI and drops down to 0 I can see an air bubble in the clear line where it leaves the pump which to me means it's no longer able to push water into the tank.

The last 2 years I've had problems where the injector near the water was clogged and the pump would only get up to around 15PSI, but it would hold that pressure. both times I took it apart and was able to knock out a chunk of rust. This year I tried clearing it out before hooking it up, and had a rust chunk fall out. So I'm not sure it is the same issue since when I've had that problem the symptoms were different from this.

I've attached some photos. One I found online which is pretty much how mine is setup. I added notes where there is a difference. Another is of the pump setup itself with some more notes. The third is the ejector on the shore.

Could it be as simple as the gauge is bad and I just didn't wait long enough to see if it would kick off? I assumed the large air bubble meant no water was flowing into the tank.

Thanks for all your help!

 

[LLigetfa]

It is not unusual for there to be a little air trapped in the pipes between the pump and the lake that takes a little time to work its way through. When that happens, the pump will hesitate. Sometimes you need to bleed off some of the air at the pump's priming hole by loosening the pipe plug. Of course, there will also be some water lost in doing that. I like to have a taller stand pipe where you have the plug. It helps to separate some of the air.

I also prefer to have the pump lower than the pressure tank's inlet. That way the water in the tank re-primes the pump rather than have the air rise to the top and go back to the pump.

 

[Derek_pied]

I made a quick video, unfortunately it is after the gauge dropped to 0. you can see the air bubble I was talking about.

It is not unusual for there to be a little air trapped in the pipes between the pump and the lake that takes a little time to work its way through. When that happens, the pump will hesitate. Sometimes you need to bleed off some of the air at the pump's priming hole by loosening the pipe plug. Of course, there will also be some water lost in doing that. I like to have a taller stand pipe where you have the plug. It helps to separate some of the air.

I also prefer to have the pump lower than the pressure tank's inlet. That way the water in the tank re-primes the pump rather than have the air rise to the top and go back to the pump.

I took a video but it starts after the gauge dropped to 0. You can see the bubble I was talking about. I added a few seconds of the air leak in the tank but it didn't pick up the hissing sound very well.

 

[Valveman]

If there was a chunk of rust in the ejector, the minute you turned it on it probably sucked up another chunk of rust?

 

[Derek_pied]

If there was a chunk of rust in the ejector, the minute you turned it on it probably sucked up another chunk of rust?

I tired to do a really good job of cleaning it out before I put it together. Got lots of small rust bits to come out as well.

 

[Valveman]

As soon as you turned it on more rust comes up. My best guess.

 

[Reach4]

As soon as you turned it on more rust comes up. My best guess.

Do you think Derek would benefit by a better intake screen/filter? High surface area to avoid clogging.

Derek, slather the joints at the lake side of the ejector with shaving cream to see if there is a vacuum leak.

I wonder if a combination pressure+vacuum gauge would help troubleshoot. A vaccume at the gauge would indicate some kind of leak.

 

[Valveman]

Just need to get rid of whatever parts are making the rust.

 

[Reach4]

Just need to get rid of whatever parts are making the rust.

He has plastic going to the foot valve according to the photo. So that would be the foot valve producing rust?

Probably, you suspect that rust is coming from the pump area and getting pumped down toward the injector.

 

[Valveman]

Chunks of rust coming from somewhere. The pump, and/or the ejector are cast iron.

 

[Derek_pied]

Chunks of rust coming from somewhere. The pump, and/or the ejector are cast iron.

I hadn't considered rust getting in there on the way down from the pump. I will take it all apart next time I am there. The thing is these current symptoms are totally different from the 2 times rust in the ejector was the problem.

Foot valve is brass(?), no rust there. I took it all apart to inspect before I put it in the lake.

I'm going to pick up a new gauge too. It's not quite 2 years old but it could be that simple.

Could there be a visible air bubble in the line from the pump to tank and it's still pumping water to the tank?

I've been thinking about switching over to a submersible. Every year there seems to be some sort of problem with this setup. As I understand it with a submersible I just drop it in the water and turn it on (with proper protection for lake debris of course).

 

[Valveman]

No there should not be a bubble in the line between the pump and tank.

A submersible is best because it never needs priming and pushing water is more efficient than sucking water.

 

[Derek_pied]

So I was up there this weekend and got it all working. It was sucking air at the ejector, enough for it to eventually loose it's prime. I wasn't able to see this before because the ejector and pump are 30' apart and I cant be at 2 places at once. After reading some stuff online I found out I wasn't installing the hose clamps properly which led to air getting in the line. The people we bought the cottage from showed us to install the clams past the barbs so that's' what we did. A bit embarrassing to find this out but I figured i should mention it that way if someone else reads it maybe they won't have to go through what I did. I've doubled up the hose clamps over the barbs and that seems to have solved the problem.

The pressure tank is shot. Once under pressure water will come out of the air valve. I think it's been like that since we bought the place because the pump cycles the same now as it always has.

Thanks all for the help, really appreciate it.

 

[Valveman]

If the tank is bad and the pump is cycling the same as always, it is cycling too much.