Short Cycling - Water Pressure Tank

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mslhrt18
Posts: 4
Joined: Wed Jun 25, 2014 7:16 pm

Wed Jun 25, 2014 8:32 pm

Hello,

My wife and I purchased a mobile home built in 1999 about 2 months ago. The water pressure initially was short cycling every 2 minutes or so before we purchased the house, so we asked the seller to have a plumber look at it. The plumber said he "made a minor adjustment" and everything was fine. He attributed the problem to de-winterizing the system and that it should go away.

The issue was still there after we moved in but not as bad as before so we ignored it. Last week, however, the water pressure began short cycling every 2 seconds. The lights flicker, and you can hear the water pump clicking on and off (the water pump is below the MH on the concrete slab).

Is this a bladder issue where we will need a new water pressure tank? Is it just that air needs to be added to the tank? Or is there another potential problem? Why didn't the original plumber see this as an issue and let us know? This is my first house so I'm kind of nervous about paying a plumber to come out and fix a problem when THAT might not even be the problem either.


DaleM
Posts: 385
Joined: Wed Apr 07, 2010 10:07 am

Wed Jun 25, 2014 9:38 pm

Could be a small leak some place. Look all over the underside of your home for puddling in the belly wrap.

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Greg S
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Location: Kingston Ontario Canada

Wed Jun 25, 2014 11:49 pm

If you are not using water and the pump is cycling you either have a leak or the foot valve down your well is not functioning properly. They tend to get sand in them and jam open.
An individual must enforce his own meaning in life and rise above the perceived conformity of the masses. (Anton LaVey)

mslhrt18
Posts: 4
Joined: Wed Jun 25, 2014 7:16 pm

Thu Jun 26, 2014 8:22 am

The cycling only occurs when the water is running.

Steve S.
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Joined: Sat Apr 21, 2007 7:41 pm
Location: Maine

Thu Jun 26, 2014 6:49 pm

Do you have a pressure gauge on the main line just beyond the tank? A very low pressure would indicate tank bladder failure. Most tanks are 30-50 or 40-60psi(cut-in/cut-out). Otherwise, it could be a number of problems i.e. with electric or water supply, with the pump, or with the pressure switch. I'm afraid you would need the services of a real professional to sort it out. Obviously the first plumber's non-specific "minor adjustment" didn't solve the underlying problem. If the the pump has been short-cycling for quite awhile, it's quite possible the pump's life may be near an end.


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Greg
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Thu Jun 26, 2014 7:37 pm

It's been years since I was on a well, but check the bladder tank first. Make sure you have air in the charged side (with the tire valve in it) and not water. If you have water the bladder is leaking and the tank is shot. Try charging with 30 -45 PSI of air.

Greg
"If I can't fix it, I can screw it up so bad no one else can either."

mslhrt18
Posts: 4
Joined: Wed Jun 25, 2014 7:16 pm

Sat Jun 28, 2014 8:42 pm

Well here's a new twist: We went out to the well cap and there is a pipe going from the cap into the ground. My parents think air passes through this to create pressure for the well pump to pump water out of the ground? Anyway, the pipe is completely snapped. Could this be the cause of the problem? Would this make the water pressure tank work overtime for nothing and us getting crap for pressure? Not sure, but it looks suspicious to me!

Steve S.
Posts: 117
Joined: Sat Apr 21, 2007 7:41 pm
Location: Maine

Sun Jun 29, 2014 7:06 am

The only "pipe" I know of near the well cap is the conduit that the electrical wires run down to the pump. I don't think that is your problem, unless of course the wiring to the pump has been damaged(shorted) and is causing intermittent pump operation.
I'm with Greg on this one...check your tank air pressure first. If you suspect that the wiring may be damaged, please have a professional plumber look at it. I watched the pros once install a new submersible pump in my drilled well...it's no easy task and requires two experienced people to handle the job.
You'll understand the complexity of this issue if you explore this website:
http://inspectapedia.com/water/ShortCycleCause.htm

mslhrt18
Posts: 4
Joined: Wed Jun 25, 2014 7:16 pm

Sun Jun 29, 2014 7:46 am

Thank you everyone so far for replying you've been really helpful! My dad is coming over today to take a look. I called the plumber that "fixed" the issue before we bought the house and he said we need to drain the tank and then check the air pressure. Does that sound right? Also, if wires look damaged, I feel like I shouldn't touch anything without a professional coming in because I don't want to further damage anything.

Steve S.
Posts: 117
Joined: Sat Apr 21, 2007 7:41 pm
Location: Maine

Sun Jun 29, 2014 7:56 pm

Yes, drain the water from the tank and make sure the power to the pump is switched off. There should be a tire(Schrader) valve near the top of the tank. With most tanks air pressure should be about 2 psi less than the cut-in pressure(if you know exactly what that is for your system). Mine is a 38psi pre-charge for a 20-gallon tank since cut-in pressure is at 40 psi. If you're unsure of cut-in pressure just add small amounts of air (5-10 psi) and retest the system to see if there is any improvement in cycling time. Don't add too much air because these tanks are rated for only so much pressure.

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