Well Pump pressure adjustment
Ken Hoover
I was working a couple of nights ago to increase the pressure in my home's
water system from the puny 20-40psi to 30-50psi (the previous owner thought he
was saving water by having such low pressure...duh). I managed to get it
raised a bit, but the dynamics of the control adjustments evaded me and I
wound up more or less messing with it until it went in the right direction.
Can some kind soul please explain how this switch works?
The pressure switch is a Square-D "Pumptrol" switch with two sets of
contacts in it controlled by a pressure line from the pump head coming in to
the botton of the switch. There are two springs with adjustment nuts on them
inside the switch, one with a large heavy spring (about 3" long) and a short
one with a much smaller spring about 1" long. Tightening the nut on the large
spring made the pump stop pumping at a higher pressure, but I never figured
out what the small spring was for... perhaps raising the cut-in pressure.
The pump is a GE jet-type pump with two lines going into the well (I assume
this is the configuration for deeper-than-normal surface-pump well) and one
going to the pressure tank.
Any suggstions would be appreciated. Please email or post responses.
- Ken Hoover
PS: The reply-to address has been mangled to thwart spambots. Please remove
the uppercase part of the address to send me e-mail.
--
Kenneth J. Hoover N3YER | "Very funny Scotty,
Systems Analyst, CEDCC | now beam down my clothes."
PSU College of Engineering | email: kj...@psu.edu spam : /dev/null
unknown
FIELD ADJUSTMENT OF PRESSURE SETTINGS
After disconnecting the power supply from the pressure switch, settings
can be changed easily. Follow this procedure: (1) Adjust cut-in point
first with the large spring. Tightening down on range spring will raise
the cut-in point. Loostyening up on this spring will lower the cut-in
point. (2) Adjust the cutout point last with the small spring.
Tightening down on this differential spring will raise the cutout point.
Loostening up on this spring will lower the cutout point.
For a type FSG (1HP rated at 120V, 1-1/2HP at 240V) the cut-in is
adjustable for 5-45PSI, and the differential is adjustable for 15-30
psi.
This gives a cutout range of 20-65psi.
However, on form M4 devices, the minimum cut-in is 19psi. (The M4 device
has a pump shutdown feature, which trips the switch if the pressure
falls
below 10psi, and when tripped, there's a manual lever on the switch that
must be reset for the pump to run again. This is a safeguard to shutdown
automatic pump operation - used to protect the pump from running dry if
the well runs out of water)
David Buxton
The pump control preassure switch has two adjustments. One sets the
preassure and I'd guess that clock wise ups the preassure. The other
adjustment controls the hysteresis. A small hysteresis means the pump
comes on frequently as the preassure is controlled over a very narrow
range, say 58 to 60. Open up the hysteresis and then lets say the control
loop is 40 to 60. A lot of wear and tear ages a pump at turn on. So, you
want a big loop. A big preassure range means lawn sprinklers behave
inconsistently and showers can be a lot more fun. So, you make the
compromise. 50 to 60 might be the right answer for you.
Jim Mais
Small spring is a differential adjustment. The differential
may be anywhere from 15 to 30 psi depending on the seting of the other
spring. Cut-in equals cut-out minus differential.
Speedy jim
Gary Slusser
Ken Hoover <kj...@psu.edu.DIE.SPAM.DIE> wrote in article
<5j33fa$j...@r02n01.cac.psu.edu>...
> I was working a couple of nights ago to increase the pressure in my
home's
> water system from the puny 20-40psi to 30-50psi (the previous owner
thought he
> was saving water by having such low pressure...duh).
A higher pressure will move water faster and cause your pump to run more
often using more electricity and putting more start up wear on the motor.
The higher the pressure the less draw down gallons. Lower pressure, less
pump cycles, less start up wear etc.
> Can some kind soul please explain how this switch works?
First you need to turn off the well pump, then drain all water out of the
tank and your plumbing if you don't have a shut off just past the tank. If
not shut off, shut off the cold feed to your water heater or domestic coil.
Then the air pressure in your pressure tank needs to be set at 29 pounds
(for 30-50 psi). Then turn on the pump and fill system with water. Then run
water and note the cut-in pressure, adjust the tall nut down to raise, up
to lower to 30 psi. Then watch the cut-out setting, adjust the short nut,
set at 50 or higher. Maintain at least 20 pounds differential. Higher is
down, lower is up. Keep this routine until you get 30-50 psi. IMPORTANT: As
you set the tall nut it automatically raises the cut-off setting. Be
prepared to turn the short nut up after adjusting the tall nut or you may
get to 75 psi or higher very quick. This is not easy if you have these two
nuts very far out of adjustment. The tall one moves BOTH cut-in and out
settings, short only the cut-out. You need a good air gauge and water
pressure gauge. The air pressure should be 1 to 2 pounds less than the
cut-in setting. I say 1 pound because as the cold water cools this air it
will lower the pressure. Just keep the cut-in slightly higher than your air
pressure. Otherwise you'll run out of water before the pump kicks in.
> but I never figured
> out what the small spring was for... perhaps raising the cut-in pressure.
No, cut-off pressure.
> The pump is a GE jet-type pump with two lines going into the well (I
assume
> this is the configuration for deeper-than-normal surface-pump well) and
one
> going to the pressure tank.
Two lines means deep well jet, good usually to about 175', single line jets
good to about 25' and they only suck water. The small line pumps water down
the well to the jet body (venturi) and the large brings some water out of
the well back to the pump along with what was pumped down.
> Ken Hoover
> Kenneth J. Hoover N3YER | "Very funny Scotty,
> Systems Analyst, CEDCC | now beam down my clothes."
> PSU College of Engineering | email: kj...@psu.edu spam : /dev/null
>
Gary