Sudden pressure drop before pump kicks in

[mikenh]

We noticed this in all the showers and a faucet so far,
All of a sudden pressure drops off to the point of releasing the diverter and the water just trickles out of the faucet, then the water pump kicks in and pressure resumes again.
The first time this happened, it wasn't enough to trip the diverter valve. Now every shower drops pressure enough to trip the valve until pressure rises and we can resume shower. The pressure drops so low that it truly is barely coming out of the faucet until the pump kicks on again in about a couple seconds.
This has been going on for about 3 days now, slightly worsening each day.
Weird but we used to complain because it seemed like the pump was always running (we have a small tank, a Well-X-Trol WX-202), and it would kick on several times during a 10-15 minute shower, now the pump seems to only kick in once during that time and the pump runs longer now until it turns off.
I recall checking it a year or two ago and the pressure on/off settings were correct as I recall. I checked the tank and pump today in operation. I missed it when it turned on, but it stopped at about 62 lbs.
The installation guide suggests the following: "... Release or add air as necessary to make the precharge pressure 2 psig below the pressure switch pump cut-in setting. (Example, if you have a WX-202-XL with a precharge of 38 psig, and you have a pressure switch setting of 30/50 psig, adjust precharge of your WX-202-XL from 38 psig to 28 psig.)..."
Again, the pressure drops rapidly, all of a sudden, then the pump kicks on.
Any help would be greatly appreciated.
Thanks

 

[waterwelldude]

Check to see if water comes out of the valve stem on the tank. If it does, the bladder in the tank is bad and you will need a new tank.


1. Turn the power to the well pump OFF.
1a. Turn off main water valve.
2. Completely drain the pressure tank.
3. Check the amount of air in the tank using the air valve on top of the tank
4. Using a small compressor, adjust the pressure to read 2-3 psi under the cut-in pressure of your pump. For example, if you have a 30/50 pressure switch,provided nobody has re-adjusted the switch, you air pressure in the tank should be set at 27/28 psi.
If the tank is out of air and will not hold air, then the bladder/diaphragm is bad and the tank needs to be replaced.
5. Turn power back on allowing the tank to refill.
6. Turn main water valve to house back on.

 

[mikenh]

Thanks for your advice. I just checked the air fill valve stem on the tank today. I let it release a short, quick blast. It had pressure with the tank full and there was no indication of moisture or water in the air released. I have a Square D 40/60 pressure switch. At full, the tank pressure is at 64lbs.
I noticed that the switch is not directly connected to the pump housing. The pressure is fed from the pump housing to the pressure switch thru a small 1/4" length of black plastic tubing. Is that normal? Any further advice?
Thanks again.

 

[speedbump]

Also check the tubing going to the switch, and the fittings on both ends of the tubing. If that stuff plugs up with minerals, it can have the same effect as an improperly aired up tank.

 

[mikenh]

Finally - Fixed!
Here's what I did and what I found.
I bought a new Pressure switch from Lowes. It is a 30-50 lb vs the 40-60 that was on the pump originally.
First I switched off power and shut off the valve on the well side. I next opened faucets to drain the rest of the pressure from the tank, left them open and drained the remaining from the drain on the tank.
The tank had about 34 lbs pressure of recharge in it empty. I emptied air from the tank to 28lbs.
Next I removed and replaced the old pump switch. The pressure feed was attached to the pump housing via an 18"in. 1/4" OD PVC tube. When I cut the tube off the 90 degree elbow of the old pump switch I could see the tube was filled with rusty goop. I unscrewed the other elbow from the pump housing and it was Packed with rust goop.
I decided to go back to the store and get a new tube assy while I was at it.
The tube assy came with new 90 degree connectors, however they were not brass, whereas the original was. I did not use the new ones.
The pressure switch came with a new brass one and I thoroughly cleaned out the other brass one that was found at the Pump housing.
I now had a mounted and wired pump switch, a PVC tube terminated with the threaded 90 degree adapters.
I peered into the hole in the pump housing now and it appeared like it could use a cleaning so I purged it with some spring water from while scraping what appeared to be a small hole.
Hmm. The hole was holding any water I poured into it.
Just to test a theory, opened the valve to the well and switch on the power for a second.
No change to the water level sitting in the hole!
I tried it again, leaving the pump on for at least 20 seconds.
The tank was filling, pressure was rising on the gauge, however no water was coming out of the threaded hole for the pressure gauge tube.
I started to clean out the hole with a small drill bit held in my hand only, and it broke thru.
The hole had been completely plugged. I cleaned the hole now and tested and finished cleaning it with the water pressure on. It finally gushed like a geyser now.
I put a few wraps of Teflon tape on the elbow and finished assembling the pressure tube to the pump housing. It was now together and ready for testing.
In testing, the 30/50 pressure switch was turning on at around 30lbs and off at 40lbs.
It needed adjustment on the cutoff end. As directed in the instructions I left the large spring loaded adjustment alone and turned the smaller one clockwise about 1.25 turns to get me at a cutoff pressure of 50 lbs.
I ran it thru a couple cycles to verify operation.
The pump is in the basement and supplied 2 floors above. The pressure was good from the top floor faucets and shower.
I suspect the pressure gauge is getting gunked up like the other stuff, but I left it as is because it still seems to be working fine. I expect I'll need to replace it in a couple years.
Since install and tuning, everything is working great!
Thanks so much to all for the help, troubleshooting and encouragement!
Hope this information helps others.