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rws
12-18-2014, 07:19 AM
I have the typical pressure tank in my house. I'm not fond of how often the pump has to cycle, the constant on/off can't be good for the pump. Where the tank is, there isn't room to go bigger, so I wonder if I could add a second tank elsewhere and be effective? Not at the end of the piping, but fairly close to the existing tank. Anyone try this?

Lew Hartswick
12-18-2014, 07:22 AM
Water or air ????
...lew...

Abner
12-18-2014, 08:00 AM
I'll assume water. What you need is called a cycle stop valve.
When we installed our well I was told 2 minutes minimum run time from low to high pressure settings. Our pump is 22 gpm so we have 2 very large and expensive tanks.
We also have a booster pump located some distance from the main well for irrigation purposes. On this I use a cycle stop valve and a small 3 gallon pressure tank.
When our 2 big tanks fail I will replace them with another cycle stop valve and a small tank.

http://www.cyclestopvalves.com/index2.html

This is a new and explains how they operate. I have watched a similar demonstration in real life using yard sprinklers inside a closed see through case and they had an amp meter connected to the motor so you could see it.
Electric motors draw current as needed to do the work required. A 1 hp pump motor will draw less than name plate amperage when you are using less than name plate hp.
http://www.cyclestopvalves.com/simple/home.php

ironmonger
12-18-2014, 09:20 AM
I have the typical pressure tank in my house. I'm not fond of how often the pump has to cycle, the constant on/off can't be good for the pump. Where the tank is, there isn't room to go bigger, so I wonder if I could add a second tank elsewhere and be effective? Not at the end of the piping, but fairly close to the existing tank. Anyone try this?

As long as the pressure controls are left as is, there is no problem adding a second tank.

Are you sure that the existing pressure tank is functioning correctly? You should be able to flush a toilet without the pump turning on. The tank bladder pressure should be about 2 PSI below the pump cut in pressure setting with he tank empty of water.

re cycle stop... before you install this contact your pump manufacturer. It seems to defy physics. YMMV

paul

Lu47Dan
12-18-2014, 09:47 AM
Adding a second tank can add capacity to the system, it is done all the time on small systems that serve the public, like trailer parks, RV parks and the like.
The main problem with adding a second remote tank is the line from the first tank to the second tank should be the same size as the line feeding the first tank from the well.
I added a 42 gallon equivalent tank in a friends new shop two years ago as he wanted to cut the number of pump cycles down on days he was open, he uses a lot of water in his business. He had an electrician add a counter to the pressure switch and kept track of the number of cycles per day, before and after we added the tank. He cut the number of cycles down by 2/3's over what he had been running. But the line that feeds the shop comes off at the tank and is 1". The same size as the line from the well. We also added a check valve to the system at the tank in the shop to prevent backflow into the house system. He is now talking of adding a bigger tank in the house to cut down on the number of pump cycles on the weekend.
Dan.

Lu47Dan
12-18-2014, 09:54 AM
Are you sure that the existing pressure tank is functioning correctly? You should be able to flush a toilet without the pump turning on. The tank bladder pressure should be about 2 PSI below the pump cut in pressure setting with he tank empty of water. paul
Not correct, if your pressure is set at 40/60. Paul, the pressure in the pre-charge on the bladder should not be higher than 29PSI.
I have installed hundreds of tanks over the years and have always set the pre-charge at 28PSI. Gives the bladder a buffer if the tank drops below cut-in pressure.
Dan.

rws
12-18-2014, 10:18 AM
Sorry, I was referring to water system. Thanks for the replies folks!

winchman
12-18-2014, 10:34 AM
Did you notice the pressure when you're using just the kitchen sink? It's over 120psi coming out of the pump. It's not clear what the pressure is at the sink faucet, though.

My limited but very unhappy experience with pressure-control valves on home water systems makes me hesitant. I was hooked to a public system one time that ran over 100psi most of the time and even higher in low-use periods. It was horrible. The pressure reducing valves I tried all worked for a couple weeks, then started leaking and/or acting only as a flow restriction. The final resolution was a solenoid valve hooked to a pressure switch to control the high-pressure flow into a tank that supplied the house at 40-50psi.

I'd get a big bladder tank (or two), and call it a day. There's no reason they won't work in parallel, and it won't matter where they are in the system as long as the piping is adequate.

ironmonger
12-18-2014, 02:19 PM
Not correct, if your pressure is set at 40/60. Paul, the pressure in the pre-charge on the bladder should not be higher than 29PSI.
I have installed hundreds of tanks over the years and have always set the pre-charge at 28PSI. Gives the bladder a buffer if the tank drops below cut-in pressure.
Dan.

see page 4:
http://www.amtrol.com/media/documents/wellxtrol/9015868_MC10185_06_12WXT_PRO_IO_NG.pdf

I don't just dream this stuff up...

paul

becksmachine
12-19-2014, 02:04 AM
see page 4:
http://www.amtrol.com/media/documents/wellxtrol/9015868_MC10185_06_12WXT_PRO_IO_NG.pdf

I don't just dream this stuff up...

paul

I agree with ironmonger. Yes, a differential of 11 psi between pre-charge and cut in pressures would provide some buffer if the tank/bladder is losing pressure over time, but it is also wasting capacity and causing more starts of the pump for a given usage of water.

Dave

Ohio Mike
12-19-2014, 10:55 AM
What are we really looking to gain here? The only energy savings is the pump start draw because the pump still has to run the same amount of time.

bborr01
12-19-2014, 12:45 PM
I had always hear the 28psi thing but I had a well repair service out this summer at my cottage and the guy charged the tank to 2psi below cut in pressure. When I asked him about it he said they always set them up this way. BTW, it is a 3rd generation well drilling outfit.

Brian

ironmonger
12-19-2014, 01:05 PM
What are we really looking to gain here? The only energy savings is the pump start draw because the pump still has to run the same amount of time.

If the tank is undersized or faulty, the pump may start every time a faucet is opened or a toilet is flushed. This causes the pump to turn on and off way to often.

I'm not a pump engineer, but I doubt that you will find a manufacturer that would recommend short cycling their equipment. So it's not a matter so much of energy conservation as protecting the pump.

If you are watering the grass or washing your car or filling the bath tub the pump will indeed run continuously and the amount of water supplied is then directly related to the well capacity and the pump GPM. Those steady state conditions are not a problem. I suspect that the problem with short cycling is related to starting current and those high currents overheating the motor. What say you motor engineers?

paul

Guido
12-19-2014, 02:18 PM
Somewhere Mr. Boucher is watching, listening and grinning. RIP, Mr. B.

Ohio Mike
12-19-2014, 03:10 PM
If the tank is undersized or faulty, the pump may start every time a faucet is opened or a toilet is flushed. This causes the pump to turn on and off way to often.

I'm not a pump engineer, but I doubt that you will find a manufacturer that would recommend short cycling their equipment. So it's not a matter so much of energy conservation as protecting the pump.

If you are watering the grass or washing your car or filling the bath tub the pump will indeed run continuously and the amount of water supplied is then directly related to the well capacity and the pump GPM. Those steady state conditions are not a problem. I suspect that the problem with short cycling is related to starting current and those high currents overheating the motor. What say you motor engineers?

paul

Exactly the if tank undersized or defective just replace it, why are we talking about adding a second tank?

Puckdropper
12-19-2014, 04:02 PM
I had always hear the 28psi thing but I had a well repair service out this summer at my cottage and the guy charged the tank to 2psi below cut in pressure. When I asked him about it he said they always set them up this way. BTW, it is a 3rd generation well drilling outfit.

Brian

The tag on my pressure tank says to charge to 2 psi below cut in pressure. I figure if they went to that trouble, that's where it should be.

deltap
12-19-2014, 04:32 PM
Short cycling? Check the tank. If a diaphragm tank , let some air out of the air charging fitting. Water released from here indicates a ruptured diaphram. An open tank loses its air over time and needs to be drained and recharged with air about once a year. Check cut in/out of pressure switch.

RoyClemens
12-19-2014, 04:40 PM
yes, I have don't even remember why I did it, but actually added two tanks about a 1/4 mile from the pump. Seemed like a good idea at the time.

Roy

vpt
12-20-2014, 10:11 AM
I always set our tanks up around 2psi below cut in as well. We use 40gallon+ tanks at our place because of the bait tanks. We also use bigger tanks because a pump that cuts in and out allot will kill itself. It is better for the pump to come on, run for as long as possible and then stay off for as long as possible. The starts are what kills pumps.

I cut up our last old tank to make a safe.

http://img707.imageshack.us/img707/8512/watertanksafe011.jpg

Leadfootin
12-20-2014, 02:36 PM
I use a pressure tank - no bladder. Recharge is by the quick and dirty method, add air when the pump comes on with nearest tap slightly open till pump shuts off. Let tap run until air comes out and/or pump comes on. If air comes out, tank is charged, if pump comes on add more air. Never add air if pressure gauge goes over about 60 psi.

Not the best method, but as I said quick and easy. Don't forget to occasionally drain the crud out of the bottom of the tank.

rws
12-21-2014, 04:35 PM
So for me to check the pressure in the tank, I would have to shut off the breaker and run the pressure all the way down?

garyhlucas
12-21-2014, 04:46 PM
In municipal water systems they put the tank at the other end of town from the water source if possible. By putting the tank on the the other end with all the service points located between the well and the pumps you effectively get water from two sources and the pressure drop during short term high flow conditions is much less. I used to build air operated packaging machines. Customers often had problems with the machines because they used a small amount of cubic feet of air but used it at an enormous rate over a 1 second or less cycle. I would prove that the problem was their air piping not the machine by hooking a portable compressor with a short hose right at the machine, without running it. The tank would accumulate air and the machine would run just fine.

ironmonger
12-21-2014, 05:10 PM
So for me to check the pressure in the tank, I would have to shut off the breaker and run the pressure all the way down?

Yes. There should not be any valves between the pressure switch and the pump, and a valve at the tank would only be a good idea where you have multiple tanks on large systems. So the only way to check the pressure is to turn off the pump and drain the tank at least.. You should have a main valve that supplies the house, and thus save draining the entire house.

FWIW the 28 psi thing probably is a hold over from the old days when the common pump on pressure setting was 30 psi with 50 psi pump stop. The low pressure setting was likely an effort to avoid installing a higher HP pump to save money. 30 psi is pretty anemic these days.

paul

ironmonger
12-21-2014, 05:16 PM
In municipal water systems they put the tank at the other end of town from the water source if possible. By putting the tank on the the other end with all the service points located between the well and the pumps you effectively get water from two sources and the pressure drop during short term high flow conditions is much less. I used to build air operated packaging machines. Customers often had problems with the machines because they used a small amount of cubic feet of air but used it at an enormous rate over a 1 second or less cycle. I would prove that the problem was their air piping not the machine by hooking a portable compressor with a short hose right at the machine, without running it. The tank would accumulate air and the machine would run just fine.

A small air tank installed at the end of a long supply hose can then feed a number of framing nailerís or such. Since they are peaky loads the tank really helps.

You can also install a small pressure tank and a check valve if you would like to install a flush valve commercial toilet... Just needs to have a raw water delivery capacity of 2 or 3 gallons. Not saying its a good thing, just possible.

paul