Well pump only works when manually turned on

[Michael McHugh]

So I can not figure this one out! Over the past few years we have replaced many parts on the well and tank including the following:

Pressure Switch and the pipe/nipple running into it
Pressure Gauge
Well Pump
Pressure tank(blue one)

Now the problem is the pressure will run out of the house and the switch will kick on at the right time but the well won't immediatly engage. If I use the lever on the pressure switch I can hold the leads closed and the pump will turn on after five seconds but otherwise I cant get the tank to fill. I have read of similar spots where a clogged nipple will make it so the switch doesnt work but we just put a brand new one on so we are clueless.

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[Michael McHugh]

 

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[Reach4]

Well Pump
Pressure tank(blue one)

Is that pump a submersible (down the well), or is it a jet pump?
The pressure tank should be sized big enough that the drawdown will keep the pump running a minute or more each time.

Now the problem is the pressure will run out of the house and the switch will kick on at the right time but the well won't immediatly engage. If I use the lever on the pressure switch I can hold the leads closed and the pump will turn on after five seconds but otherwise I cant get the tank to fill. I have read of similar spots where a clogged nipple will make it so the switch doesnt work but we just put a brand new one on so we are clueless.

You need to set the air precharge for the pressure tank to 2 PSI below the cut-on pressure if you have a submersible pump, and typically 4 psi ( or a bit more if needed) for a jet pump. A jet pump takes longer to deliver water.

You bought the kind of pressure switch with a low pressure cutoff. That is designed to shut down the pump if the water runs out or if the pump cannot build the pressure for some other reason. I think most pressure switches don't have that feature. The suspicion is that your pressure tank may be empty before the pump can deliver enough water to keep the water pressure above the 20 PSI.

To set the air precharge, stop the pump and open a faucet until the water pressure is near zero. Since the prime theory is that you have too much precharge, you may not need to use an air pump/compressor this time.

If you want to check that your air pressure gauge and water pressure gauge are in calibration with each other, when the pressure is steady up in the middle of its normal range, the air pressure will be close to the water pressure.

Edit: Your video was interesting. I have never seen one of those low pressure cutoff switches work. I was surprised that it opens in slow motion compared with the snap action that I am familiar with.

 

[Valveman]

If the points in the switch are touching when the pressure drops to 40 or start pressure, then the pump is getting power. Do you have one of those SQ type pumps? They take 5 seconds to start.