I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

You need to charge the tank with the pump off and a faucet open. Sounds
like you're water logged.

--
Steve Barker




wrote in message
oups.com...
I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

On May 10, 10:56 pm, "Steve Barker"
wrote:
You need to charge the tank with the pump off and a faucet open. Sounds
like you're water logged.

Pressure tank is charged to 38 Lbs, and not heavy - so assume not
water logged. That's why I was suspecting a leak.

On May 10, 8:06 pm, wrote:
On May 10, 10:56 pm, "Steve Barker"
wrote:

You need to charge the tank with the pump off and a faucet open. Sounds
like you're water logged.

Pressure tank is charged to 38 Lbs, and not heavy - so assume not
water logged. That's why I was suspecting a leak.

Check valve? Tom

wrote in message
oups.com...
I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

Between the pump and the house or between the pump and the foot valve.
Or the foot valve (if any) could be bad.

Bob

On 10 May 2007 19:44:21 -0700, wrote:

I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

First, your pressure tank should be charged to 2 lbs less than the cut
*in* pressure. So if your pump comes on at 20, the tank should be
charged to 18 when completely empty of water. If your cut-in pressure
is 40, then you're ok, but you said the pump stops at 40, so that
doesn't sound right.

Try disconnecting the line to the house and blocking the end from the
tank. (You should have a valve here anyway...) If it builds and holds
pressure, you have a leak in the line to the house.

If it still cycles, you have a leak on the source side, or a bad foot
valve or check valve.



HTH,

Paul

On May 10, 7:44 pm, wrote:
I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

Others have covered all the points so I will just wrap it all up in
one:

1. Your pre-charge tank pressure is too high. Drain tank and re-
charge to 20 psi. If the problem stillpersists:

2. Leak? Quit possible, in the input line or a footvalve or check
valve. You can install a new checkvalve just prior to the tank. It
will work just fine.

I have assumed (I know, I know) that the pressure tank is in the
cottage. If it is co-located with the pump then the leak could be on
the house side and in that case you will have to find and fix it.

Harry K

On May 10, 7:44 pm, wrote:
I pull water from a lake and pump it up to my cottage. For some
reason, my pump has started short cycling. I changed the pressure
switch, and the pressure tank is fully charged (about 38 lbs). It is
primed. If I open the prime port and turn the pump in it shoots water
high into the air - getting water is not the problem.

When the pump comes on, it quickly builds pressure to 40 lbs and then
shuts off, pressure immediatley drops to 20, pump comes on, then off
very rapidly. Would a leak in the line between the jet pump and the
house cause this? I am thinking it might have frozen and split....

Others have covered the problem and solution. I am just wrapping it
all up in one:

I am assuming the pressure tank is in the house:

1. Your pre-charge in the tank is too high. Drain tank and re-charge
to 18psi. If that doesn't cure it, then you have a leak.

2. The leak will be either in the inlet pipe to the tank. It can be
a broken pipe, a bad footvalve or a check valve. You can fix the
problem by installing a new checkvalve just prior to the tank. The
system will work just fine as long as the pump doesn't loose prime but
if it is a broken pipe you will be pumping a lot of water out of it
every time the tank fills. May not matter

Now if the tank is co-located with the pump, then you have to find the
leak and fix it. Start witht he foot valve. If it is in the pipe
going to the cottage, you'll have to dig it up and fix.

Harry K

On 10 May 2007 20:06:43 -0700, wrote:

On May 10, 10:56 pm, "Steve Barker"
wrote:
You need to charge the tank with the pump off and a faucet open. Sounds
like you're water logged.

Pressure tank is charged to 38 Lbs, and not heavy - so assume not
water logged. That's why I was suspecting a leak.

It's easy to detect a leak. Shut off everything in the house.
Preferably shut off the main valve in the house (if there is one).

Pump up to full pressure, then watch the pressure gauge. If it slowly
drops, you got a small leak. If it drops quickly, you got a big leak.

I also think you are waterlogged. Empty the tank completely and drain
the lines. NOW check the tank air pressure. Close all drain valves
and restart the pump.

On May 11, 8:49 pm, wrote:
On 10 May 2007 20:06:43 -0700, wrote:

On May 10, 10:56 pm, "Steve Barker"
wrote:
You need to charge the tank with the pump off and a faucet open. Sounds
like you're water logged.

Pressure tank is charged to 38 Lbs, and not heavy - so assume not
water logged. That's why I was suspecting a leak.

It's easy to detect a leak. Shut off everything in the house.
Preferably shut off the main valve in the house (if there is one).

Pump up to full pressure, then watch the pressure gauge. If it slowly
drops, you got a small leak. If it drops quickly, you got a big leak.

I also think you are waterlogged. Empty the tank completely and drain
the lines. NOW check the tank air pressure. Close all drain valves
and restart the pump.

The pressure in the bladder should be 2lbs less than what ever you
want the pump to turn on at. Check the air valve if you have water
replace the tank