surf more
Senior Member
- Location
- eastern NC
how many of yall change them out ??say for like a bladder tank for a water pump.
pressure switch
- Thread starter surf more
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peter d
Senior Member
- Location
- New England
The well guys usually handle them around here, but I changed the one out at my parent's house. It's not exactly hard to do.
electricalperson
Senior Member
- Location
- massachusetts
i also change them out. just need a wrench and some teflon tape
be careful..some are "tricky". Some have a "0" pressure safety. Instead of working like a "norkmal" switch..low pressure on, high pressure off...yhey jad a 0 pressure off also..so if a line breaks the pump will not keep running. The switch allows you to "bypass" the 0 to get pressure... a little trickey compared with a normal pressure switch.
Cow
Senior Member
- Location
- Eastern Oregon
- Occupation
- Electrician
We have quite a few wells out here, so we change pressure switches pretty regularly. I always take a liquid filled pressure gauge with me too. 8 times out of 10 it also needs replacing.
- Occupation
- Licensed Electrician
Do the job for a relative or buddy needing a favor the first couple of times. Make sure at least one is in an old well house with cob webs and abundant rodents, then you'll be ready for prime time.
ptonsparky
Tom
- Occupation
- EC - retired
Well guys usually do them here, but they are a no brainer. Don't just change it and walk away though. Watch it cycle a few times to be sure there are not other problems. "ON" time should be at least a minute. Rapid cycling indicates not enough air in the tank or a leaking check valve. Pressure switches do have a hp rating so one size does not fit all.
Rapid cycling indicates too much air pressure in the tank, or a flooded tank due to a ruptured diaphram in the tank.....I guess this could mean "not enough air".:smile:
A leaking check valve will cause more frequent cycling, with the frequency depending on the serverity of the leak.
The air pressure in the tank should be checked with the pump not running, and zero water pressure in the system....faucet open, drain the water pressure down completely.
Set the air pressure to 2 lbs below pump cut-in pressure...ie....if you set the switch to cut the pump on when the gage drops to 20 psi, the air tank should have 18 lbs air pressure when the water is at zero pressure.
This allows the air resevoir inside the tank to always remain slightly compressed, and prevents the air bag (or diaphram) from hitting the bottom of the tank and being damaged when the water pressure falls to 20 psi (cut in).
The differential pressure (switch cut in-cut out) should be set as high as possible, with the high side dictated by customer preference, pump capacity, and the ability of the plumbing system to handle the high pressure.
This results in fewer pump cycles for a given output of water.
Fewer cycles = Longer pump life and lower power consumption.:smile:
Most residential systems that I see have a cut in of about 20 lbs. and a cut out pressure of around 50 lbs.
On the pressure switches that have a "zero pressure' safety cut out, the switch will require manual reset if the water pressure ever drops below the (preset) switch cut-in pressure.
This is to prevent the pump from running if the well is dry, or if there is a leak in the down pipe into the well, either of which can cause the pump to run continuously (or dry) and be damaged.
To reset the switch, you must gradually move the reset lever until the pump starts to run, and hold it in that position until the pump achieves cut in pressure on the switch. At that point, the switch will latch, and you can then turn the lever to the full on position.
You can't simply reset the lever because without pressure on the system, the switch won't latch.
I didn't mean for this post to be so long, but some of the info may be helpful if you work on well pump systems.
steve
very helpful, Steve. Thanks!
I wish I had read it before the first time I encountered a zero pressure switch"
Being too old and stubborn to read instructions, and having changed out dozens of pressure switches in industrial applications, that lil switch gave me an opportunity for some lengthy field training.:smile:
I wish I had read it before the first time I encountered a zero pressure switch"
Being too old and stubborn to read instructions, and having changed out dozens of pressure switches in industrial applications, that lil switch gave me an opportunity for some lengthy field training.:smile:
surf more
Senior Member
- Location
- eastern NC
nice--thanks for the very detailed info!!
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