I have a drilled well (that is, not sand point) with a jet pump and pressure tank. Today the pump started turning on even though no water was being used. Watching the pump pressure guage, once the pump shuts off, the pressure ever so slowly drops until it engages.
I have branch-isolating ball-valves in my system so I was able to reduce the pipe system to just the main line and the pressure tank. I inspected the main line for leaks, and there are none.
I have an isolatin valve on the pressure tank too. When I close it, the pressure guage on the pump drops more quickly. When I oprn the valve again, I hear water rush out of the tank and the pressure jumps back up, then continues to drop slowly.
In other words, it sounds to me like my foot valve is allowing back-flow. Either that or I have a leak in the pipes on the well-side of the pump.
But I have a couple of questions:
1) I would have thought that the pump itself prevented backflow from the plumbing system. That the foot valve served only to stop the water in the inlet pipes from back-flowing. If ths is true, then it may just be my pump. Can someone tell me if jet pumps are supposed to allow back-flow?
2) If it is my foot valve, just how hard is it to change one? I mean "hard" in the sense of, are there any special tricks or tools required. It seems to me that it should just be a matter of pulling the well cap, pulling up the hoses, clamping on a new foot valve, lowering it back down, and priming the lines ready to go - - but I may just be ignorant of some subtlety that makes it impossible for me.
3) The other variable for consideration is cost - if the labour to do this is usually just ~$100, I'll just fcall someone. If a foot valve is $50 but the labour is $1,000, I'll learn how to do it and do it.
A fot valve is only used on a jet pump. Submersible pumps have an internal or external check valve. If either leaks you lose pressure. If the line of fittings leak, you lose pressure. Neither type pump stops water flowing from through tem backwards.
To pull the drop pipe in the well can take special tools and experience, it depends on what material your drop pipe is made of and how deep it goes and if you have a pitless adapter and the well cap is above ground etc.. If you have a two line deep well jet, the drop pipeS (a pair) can be as long a 180'+/- and heavy. They can be 20' sections of galvanized adn will be 1" and 1.25" diameter wit hcouplers to undo. PVC same thing but the cuplers could be cemented rather than threaded. If coiled PE tubing was used, it's the lightest and used insert/barbed fittings with hose clamps; about the easiest to work with but the longest to deal with.
I don't charge time and materials, so I ask about the well and base the charge based on what I preceive as the difficulty of the job and I don't dig. S oif the casing isn't above ground I withhold my quote until I know what the top of the casing looks like and how deep it is. Buried sanitary seals can difficult to remove.
My advice... if you have that type well (or not) and pull the drop pipe(s), put a pitless adapter and submersible pump in and extend the casing above ground at the same time. Don't call a plumber unless s/he knows wells, look for a pump guy or well driller.
Quality Water Associates