A friend has a shallow well with a jet pump in the basement. The pump
is a Wayne brand. I have done plumbing for years and this one has me
stumped, so I thought I'd toss it on this newsgroup and see if anyone
can make sense of it. I should note that I rarely run across these
jet pumps anymore because most people have deep wells with
submercibles these days. But this guy only has a 40' deep well on a
rural farm, and gets plenty of water.
He had no gauge on the pump and has been getting air in the lines in
the house. Constant spitting and sputtering from the faucets. The
well has plenty of water, so I thought there was a leak somewhere in
the pipes in the well. That was until I took a closer look at the
pump using a trouble light, not just a flashlight. since his basement
lights did not work because all the pull chains were broken off. (the
guy is not handy in the least).
That's when I noticed that the clamped fitting where the well pipe
attaches to the pump was leaking a slow but steady drip. Tightening
the clamps did not help, so I replaced the barbed fitting and cut off
the end of the pipe which was really torn up from the clamps. That
solved the air in the lines.
I decided to put a gauge on the pump while I was doing the job, only
to find that every pump I have ever worked on has 1/4" pipe plugs for
gauges and other accessories. NOT THIS PUMP. It has 1/8" plugs. The
pressure switch is not screwed into the pump, but mounted on the motor
and attached to the pump by a tiny hose, with a 1/8" fitting. The
pump only has two more plugs. One is above the tiny hose to the
pressure switch, the other directly below the inlet pipe from the
well, and there is not enough room there to put a guage.
I chose the only workable plug, (above the pressure switch hose)
removed it, and using a 1/4' to 1/8" reducer, installed the guage.
The pump was primed and turned on. The guage showed ZERO pressure the
whole time the pump filled the tank. I am standing there watching it,
knowing by the sound of the pump that it IS pumping the tank full, and
wondering why the heck the gauge is still reading zero. Then the pump
stopped and it instantly jumped up to about 50lbs of pressure. As I
drained water from the tank, the gauge slowly dropped until it reached
a little below 30lbs and the pump kicked ON. Immediately the gauge
dropped to ZERO.
I have never seen anything like this. Why the heck does the gauge
drop to zero while the pump is running and show the actual pressure
after the pump stops? This is just too weird.....
Yes, I have considered placing the gauge in the line going to the
tank, but did not feel like ripping pipes apart at the time. However,
this still leaves me with this unanswered question of why the gauge
drops to zero when the pump is running.
By the way, I did install some new light fixtures so the guy can see
in his basement again...