Pump runs continously but doesn't build enough pressure to reach cut-off

[Bhavdeep]

Hi I have a well system. Well pump is a submersible 4" 7GPM 3/4HP pump installed about 150-160 ft deep in a 200 foot deep well. The pump was replaced in 2012/2013 timeframe. The well is about 100 feet away from the pressure tank in the basement and is connected via a 1.5" pvc pipe buried below the frost line (Maryland area).. For the last couple of months I hear my pump run continuously whenever I am outside but I assumed it was because maybe something was using water in the house. However, recently the shower on the 2nd floor has very low water pressure.

Yesterday I checked the pressure switch specs in the basement and it was at 30/50 and not stuck. The water pressure never built up past 30 PSI. I then checked the air pressure in the pressure tank after draining it and it read 30 psi (used a tire gauge - probably not completely accurate). I then closed my supply side valve after the Tank Tee and turned off the pump by switching it off at the wall power switch. Pressure on the tank tee gauge instantly dropped to zero. I cannot figure out why the pressure dropped since there is nowhere for the water to go since the house supply side valve is closed and the check valve just before the tank Tee wouldn't allow the water to flow backwards. The check valve is new - it was installed about a year ago and it is correctly installed (flow direction). I am at a loss where the pressure went?

As a second separate test, I closed everything , turned on the pump and allowed the system pressure to build up - after about 2 minutes it got to 30psi and stayed there for 5 minutes without shutting the pump or the pressure switch off. Then I turned the pump off and drained the pressure tank into a 3 gallon bottle and hardly a quarter gallon of water came out and it dropped to zero in less than a minute. As a third test, I opened the tank tee outlet bib and ran the hose back into my 3 gallon water bottle and turned the pump on to fill the gallon bottle. The bottle filled up to 3 gallons in 37 seconds I repeated the test twice so I could confirm that the well pump is running and pumping at about the rate of 5 gallons per min. See pictures of setup.

I have been in the house for over 15 years. It used to generally run about 40psi since I had hooked up the pressure gages to my water softener system 3 years ago. Something is wrong and I just cannot place my finger on it. I'd like to know how to proceed to check what's causing the well pump to run continuously and not produce the pressure is used to do. I don't want to replace parts unnecessarily. Would appreciate any help the experts and pros on this forum can provide.

 

[Reach4]

How much current is going through one of the hots when the pump is on? If high (more than 7 amps) expect a hole in the pipe down the well but the problem could be a bad pump. If low, expect the pump is bad.

When you get a new pump, I would get rid of that check valve that you have now. Altho if it is a hole in the pipe, the check valve kinda works around it.

Until you get it fixed, maybe try to adjust the pressure switch to 15/25 or so, and reduce the precharge to maybe 13. But that is just a workaround.

 

[Sponsor]

 

[Valveman]

Most likely a hole in the drop pipe, which will be right above the check valve on the pump.

 

[Greenmonster123]

Most likely a hole in the drop pipe, which will be right above the check valve on the pump.

Why do holes form there?

 

[Valveman]

Why do holes form there?

Usually there is a steel nipple screwed into a brass or stainless check valve or pump. The dissimilar metals causes electrolysis that eats a hole in the steel fitting. Wrapping the steel nipple with a little electric tape will keep this from happening, but few people know that. Not using anything steel is also a good way to prevent it. Also, the check valve at the tank, that is not needed, can cause a pressure spikes that hastens the formation of a hole.

 

[Bhavdeep]

Until you get it fixed, maybe try to adjust the pressure switch to 15/25 or so, and reduce the precharge to maybe 13. But that is just a workaround.

Thanks for the quick responses. I'll do the amp test and post back. I am still curious that if the check valve (the one in the picture just before the T) works the water should not have flowed back even if the pump is on and the tank pressure should not have dropped - how would a hole in the drop pipe account for the drop in the tank pressure?

Also, if I lower the tank pressure to 15/25 will that be enough pressure to get the water to the upstairs shower - it's a pretty big house and the shower head is about 28 feet higher than the well tank T and about 70-80 feet of horizontal run to get to the shower head. Also shouldn't the differential be 20psi as per my tank specs (Goulds V260 tank - 85 gallons)?

 

[Reach4]

Picture a garden hose driving a sprinkler. Suppose somebody runs over the hose with a lawn mower, and puts a big hole in the side of the hose. You expect the pressure to drop, and the sprinkler to not spray as far then.

You lose less than 0.5 psi per foot of rise. But that shower will not spray at its normal level.

This is only an interim measure. Call the well service guy, and schedule service. But he may be booked up for a week or so. The alternative to dropping the pressure setting is to turn off the breaker when you are not actually using water.

Typical pressure switch drops both cut-in and cut-out pressures by about 10 psi when you turn the nut on the big spring 3.5 turns CCW. So your existing switch may not be able to be lowered enough for this workaround.

 

[Plant.One]

Usually there is a steel nipple screwed into a brass or stainless check valve or pump. The dissimilar metals causes electrolysis that eats a hole in the steel fitting. Wrapping the steel nipple with a little electric tape will keep this from happening, but few people know that. Not using anything steel is also a good way to prevent it. Also, the check valve at the tank, that is not needed, can cause a pressure spikes that hastens the formation of a hole.

thats exactly what happened to mine.

dime size hole in the steel nipple. the pump was just recirculating water into the well casing nonstop and would never build enough pressure above the check valve for the pressure switch at the bladder tanks to shut it off. ended up killing the pump.

damn elecric bill was double the whole time due to the pump running 24/7. didnt figure out why until too late.

 

[Bhavdeep]

thats exactly what happened to mine.

dime size hole in the steel nipple. the pump was just recirculating water into the well casing nonstop and would never build enough pressure above the check valve for the pressure switch at the bladder tanks to shut it off. ended up killing the pump.

damn elecric bill was double the whole time due to the pump running 24/7. didnt figure out why until too late.

check the amp draw on 1 leg of the 230V 2 wire feed to the pump. it's drawing 7.9Amps which seems to be on spec for a 3/4 HP motor. Now i'm thinking i have to pull the pump to find the leak and hope it's in the check valve , nipple, pitless adapter or drop pipe and not in the underground piping beneath my driveway and concrete walkway to the house

 

[Reach4]

1. Will pull the pump yourself?
2. Do you have a pitless adapter?
3. What is the diameter of your casing?

 

[Valveman]

check the amp draw on 1 leg of the 230V 2 wire feed to the pump. it's drawing 7.9Amps which seems to be on spec for a 3/4 HP motor. Now i'm thinking i have to pull the pump to find the leak and hope it's in the check valve , nipple, pitless adapter or drop pipe and not in the underground piping beneath my driveway and concrete walkway to the house

7 amps for a 3/4HP means it is a big leak. Most likely not underground or you would have seen a lake by now. Usually from a hole in a steel nipple between the pump and check valve or a steel adapter to the drop pipe. Wrap it with electric tape next time.

 

[Bhavdeep]

1. Will pull the pump yourself?
2. Do you have a pitless adapter?
3. What is the diameter of your casing?

1. I am planning to pull the pump myself with some help ..
2. I assume I do have a pitless adapter - have not actually opened the well cap to look down
3. about 6" diameter casing

 

[Bhavdeep]

7 amps for a 3/4HP means it is a big leak. Most likely not underground or you would have seen a lake by now. Usually from a hole in a steel nipple between the pump and check valve or a steel adapter to the drop pipe. Wrap it with electric tape next time.

I checked online and it said between 7-8 amps for a 3/4 HP pump (230V, 2 wire single phase) - if you think it's too much current what should the amp range be?

 

[Bhavdeep]

I checked online and it said between 7-8 amps for a 3/4 HP pump (230V, 2 wire single phase) - if you think it's too much current what should the amp range be?

this reference also has it listed between 6-8 amps... https://www.lockewell.com/forum/viewtopic.php?f=24&t=200

 

[Reach4]

Consider adding a flow inducer sleeve to your pump, to increase the life of the motor, tho that was not the problem for you this time. Search for inducer with the search box above.

 

[Valveman]

I checked online and it said between 7-8 amps for a 3/4 HP pump (230V, 2 wire single phase) - if you think it's too much current what should the amp range be?

It is not too much current, but is is max for a 3/4HP. That means the hole is large and letting out a lot of water. If the amps were low, that would mean the pump is worn, the screen or pipe is clogged, or the well is out of water.

 

[Bhavdeep]

Thank you for the explanation on the pump current draw. Since I am going to pull the pump to find the leak, I am strongly considering replacing the pump. It's about 9 years old and since then I have put in a water neutralizer, water softener, a 75GPD RO system and my outdoor lawn irrigation system which has 26 zones and probably sized to run at about 10GPM at 40 PSI. I normally just try to run the irrigation system very early in the morning or late afternoon when the rest of the water demand inside the house is low but with the softener, neutralizer and RO system I still have low pressure issues if things are running concurrently.

My well specs are 200ft deep well, static water level is at 14 feet; pumping water level is at 23ft; was tested to flow @ 20GPM within 5 minutes by the well drilling company in 2005. The well was set at about 170 -180 feet down in the well according to the well company. I have not verified any of these specs provided to me by the well company from their 2005 records. The supply pipe from the well to the pressure tank is about 100 feet and is 1.25 or 1.5 in I believe (I measured the outside circumference of the supply pipe to be 6.4in). The pressure tank is Goulds V260 (85 gallon pressure tank with 26 gallons drawdown at 40psi). The existing wire to the pump is 12 gauge 2 wire.

Please see the pictures of the set-up inside the house.


The one plumbing company I spoke to this morning suggested I should get a constant pressure pump system but on the phone they quoted about $3500 and I am also not sure if they could install it with the 2 wire pump wiring that I currently have. I don't want to tear out parts of my driveway and concrete walkway out.

I would like to get a pump that will get me approximately 20GPM with a 40-60 pressure switch and my existing tank and wiring set-up. The Goulds 18GS15422C seemed to be a good fit based on it's pump curve; however, I would like to know if there would be a better pump recommendation or what other people would calculate or spec.

 

[Valveman]

This is where most people jump from the frying pan into the fire. Lol! Going from a 7 GPM, 3/4HP to a 18 GPM, 1.5HP is a good idea to get more volume and pressure. But your sprinkler system that was taxing a 7 GPM pump was keeping it running constant, where the larger pump will cycle itself to death if you don't make some changes.

Making all your sprinkler zones 24 GPM would be one way. That is because a 18GS15 lifting from 23' will deliver 24 GPM at 60 PSI. If you are not using 24 GPM on every zone, the pump will cycle itself to death. Making every zone 24 GPM will solve the cycling problem, but is using all the water the pump can produce, and you won't have any pressure in the house.

Adding at least one more of those large and expensive tanks is another option. But that will just cause the pump to cycle every 2 minutes instead of every minute. Still lots of cycling, and the pressure will continually be going up and down from 50 to 70 over and over.

Variable speed drives or VFD's are the "elegant" way to handle these problems. Put in as large a pump as you want, and a VFD will make it deliver constant 60 PSI at any flow rate. And yes they make 2 wire VFD's these days, just for "your convenience". Lol! VFD's also come with an "elegant" price tag, need to be replaced often, and are hard on the pump and other components. All pump companies push VFD's these days, because they are the most profitable thing in the pump industry. But that is not a good thing for the consumer.

Adding a simple Cycle Stop Valve will deliver the same constant pressure and variable flow benefits of a VFD, without any of the negative side effects and high cost. The CSV1A or CSV12560-1 will work with that size tank, although you could replace it with as small as a 10 gallon size if you wanted or needed to replace the tank. With a 20 GPM, 1 HP pump the CSV will vary the flow from 1 GPM to 24 GPM while maintaining 60 PSI constant. Just make sure not to put in a nipple that will rust out down hole as the CSV will make the pump last a lot longer than 9 years next time.

 

[Bhavdeep]

Thank you I will look into the Cycle stop valve...meanwhile, i have had my lawn sprinkler system switched off since early Sep (it gets pretty cold , wet and snowy here in the mid-atlantic) so it's not contributing to the pump issue I am having at this time. Today I took off the well cap to look inside the well and I was surprised to see water swirling at the top... goes more to your earlier theory of a leak but since the water is swirling near the top I assume the leak is also near the top - regardless the pump will have to come out to fix the leak. I took a video of the water swirling and posted it at the link below..

 

[Valveman]

Lol! Yeah I believe your hole is close to the top of the well. Maybe even just the o-ring in the pitless adapter.