Cycle Stop Valves

Pump System Questions and Answers => Applications => Topic started by: dave4333 on August 18, 2020, 11:08:51 AM

Title: Cycle Sensor application
Post by: dave4333 on August 18, 2020, 11:08:51 AM
We have a well which produces 4.5 gpm and a pump which pulls 5 gpm so a net deficit of 0.5 gpm. We have an irrigation system too. I am trying to prevent pump from running dry. The well has a reserve of about 600 gallons (450 feet deep with 40 foot static level).

I have a Square D pressure switch with low pressure cut off. The switch is 40/60 so it cuts off below 30 psi. We also have a 90 gallon Wellmate tank. We have had no issues until the other morning when we had no water. Pressure switch had cut off. I’m not sure if it was truly a low pressure situation or a glitch with the switch. It happened in the middle of the night.

Would the Cycle sensor be a good solution for our situation? Also, what would be the benefit of a cycle stop valve?
Thanks
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 18, 2020, 11:25:56 AM
If you have a 10 GPM pump and it is cycling on and off while using 4.5 GPM, then yes a CSV would help.  A 90 gallon tank holds about 20 gallons of water, and your 10 GPM pump is probably running about 2 minutes to fill that tank.  That would take 4 minutes to fill while using 4.5 GPM.  But while you are using 4.5 GPM the pump is still producing 10 GPM and filling the pressure tank.  So your pump is basically pumping 10 GPM for 4 minutes, then it is off for 4 minutes while the tank supplies the sprinklers.  It is easy to pump a 4.5 GPM well dry when filling a pressure tank at 10 GPM for 4 minutes at a time.

A CSV would turn your 10 GPM pump into a 4.5 GPM pump.  The pump would draw a steady 4.5 GPM from the well while you are and because you are using 4.5 GPM.  There is no extra water produced to fill the tank and or pump the well dry.  There are many benefits to drawing a steady 4.5 GPM from the well compared to 10 GPM for 4 minutes then nothing for 4 minutes.  The big tank is also just seen as another 20 gallon demand that must be filled after the sprinklers are off and before the pump will shut off.  That extra 20 gallons to fill the big tank could be when you are pumping the well dry.

The low pressure cut off switch does not always protect a pump from running dry.  The 40/60 switch needs the pressure to drop to 30 before it can shut the pump off when the well is dry.  But if the sprinklers have been turned off and you are filling a pressure tank when the well pumps dry, the pressure will not drop to 30. the pump will not be shut off, the pump/motor will just get hot and be destroyed.

A Cycle Sensor is much better protection for a dry well condition as it doesn't look at pressure.  It looks at amps and knows when the pump is running dry.
See this.
https://vimeo.com/248374357
Title: Re: Cycle Sensor application
Post by: dave4333 on August 18, 2020, 11:50:24 AM
I’m sorry. Our pump only pumps 5 gpm not 10. How would all of that affect our situation and application? Thanks
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 18, 2020, 12:06:34 PM
Even a 5 GPM series pump will produce about 9 GPM at low pressure.  5 GPM is just the sweet spot in the pump curve.  It will do more than that.  So just change my figures to 9 instead of 10 GPM.  You can tell by how long it takes to put 20 gallons in that 90 gallon tank?
Title: Re: Cycle Sensor application
Post by: dave4333 on August 18, 2020, 12:23:16 PM
Interesting. I actually timed it, and it took about 2 minutes, 40 seconds. I will definitely purchase the cycle sensor. I still don't quite understand the cycle stop valve. With a 40/60 pump setting and tank set at 38 psi precharge, what would be the correct valve to use? Pump is 1 hp. would it be a 50 psi valve?
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 18, 2020, 01:05:57 PM
The CSV12550-3 would work with a jet pump.  The CSV12550-1 would be needed for the submersible.  But the CSV1A would be best and would work with either pump. 

Here is a link to a video which should help you see how the CSV works.

https://vimeo.com/248374194
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 18, 2020, 01:07:10 PM
Interesting. I actually timed it, and it took about 2 minutes, 40 seconds. I will definitely purchase the cycle sensor. I still don't quite understand the cycle stop valve. With a 40/60 pump setting and tank set at 38 psi precharge, what would be the correct valve to use? Pump is 1 hp. would it be a 50 psi valve?

Measure how much water you get out of the tank before the pump starts and you will know how many GPM's the pump is putting out.
Title: Re: Cycle Sensor application
Post by: dave4333 on August 18, 2020, 03:37:16 PM
I will check this weekend as it’s a weekend place. First time ever with a well. Just had it fractured. Went from 1.5 gpm to 4.5 gpm. Want to protect pump. When a given sprinkler zone runs, pressure drops to 40 and pump comes on. Pump runs continuously with pressure in system hanging around 45 psi. Once zone shuts off, pressure rises to 60 and pump stops. It sounds like for this application, CSV would give a constant pressure of 58 psi unless pump couldn’t keep up? I will definitely order the Cycle Sensor. I’m just trying to figure out which CSV I might need.
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 19, 2020, 06:54:48 AM
Sounds like your pump is producing more than 9 GPM?  You will need the CSV1A for this system.
Title: Re: Cycle Sensor application
Post by: dave4333 on August 19, 2020, 07:32:18 AM
I'm wondering if you could help me interpret some results. Our well is about 500 feet deep. Pump is set at 450 feet.. Before fracturing, water level was 90 feet. We just had a well test done. We get 4 gpm at 380-440 feet and 0.5 gpm at 220 to 280 feet. With the well test, Yield was 4.5 gpm, Time to recover is 2:28. Recovery is 40 feet. and static level is 22 feet. I'm not quite sure what all of the above means.

I was thinking about the CSV 125. This would be in an unfinished basement. If it gets waterlogged, how much water would weep out at any given time? Are we talking about just a little spot on the floor or a drip? And, if my pressure switch is 40/60 and tank is 38 PSI precharge, would I get 60 psi valve and just increase cutout of switch to 62 or so, leaving precharge at 38?
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 19, 2020, 09:01:41 AM
Yeah doesn't make a lot of sense to me either.  If the well is only making 4.5 GPM from 440', it doesn't make sense that it will recover to 22' static in 2.28 minutes?  Recovering from 440' to 22' in 2.28 minutes would be a recovery rate of 252 gallons per minute?

Yes the CSV125 would work, but you would be better off with the CSV1A for such a small pump and in a basement.
Title: Re: Cycle Sensor application
Post by: dave4333 on August 19, 2020, 09:05:11 AM
I believe it recovers in 2 hours 28 minutes. Not sure what that would make for gpm. Approximately 400 feet at 1.47 gal per feet, divided by 148 minutes = 4gpm?
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 19, 2020, 12:05:28 PM
OK that makes sense.
Title: Re: Cycle Sensor application
Post by: dave4333 on August 19, 2020, 01:55:40 PM
I guess I'm just trying to figure out the benefit of the CSV. In my situation, it would keep water pressure constant. If we were using anything like a shower or sink, the water would come out as normal and once pump came on, it would bypass tank and pump would run continuously. However, where pump might not be able to keep up (sprinkler zone + shower), we would notice a drop in pressure?
Title: Re: Cycle Sensor application
Post by: Cary Austin on August 19, 2020, 04:19:12 PM
Ok now we are back to how many gallons per minute does your pump produce?  Whatever size pump it is, it will produce more when the water level in the well is high, and less as the water level pulls all the way down the way it does on a 4.5 GPM well.  It really doesn't matter if it is 9 GPM, 14 GPM, or 17 GPM.  The pump is still putting out more than 4.5 GPM, which is all the well will make.  To irrigate and not draw the well dry you need to use 4.0 GPM or less.  When using 4 GPM while the pump is producing 9, 14, or more GPM, the pump will be cycling on and off while the pressure tank is filled and drained.  This is bad for the pump and the well itself.  You are basically surging the well up and down by drawing 9 GPM, then nothing, over and over, while cycling your pump to death at the same time.  That is what the CSV can solve for you.

However, now we need to know what size pump you have and how much pressure it can build when the water level starts out at 22' deep?  Sometimes a pump that will still work from 400'-500' will build more pressure than a CSV or your pipe can handle.  We can double up on the CSV's and stair step the pressure down as needed.  Then we just need to make sure the pipe can handle that pressure.  And usually it can for the pump to be set so deep to start with.
Title: Re: Cycle Sensor application
Post by: dave4333 on September 03, 2020, 02:22:15 PM
I checked the tank. Cycle Sensor now installed. Tank is 90 gallon Wellmate. 24 gallons. Takes 2 minutes 40 seconds to fill. Would CSV increase back pressure on well poly pipe beyond limit? Pump is 5 gpm, 1 hp. Static level is 22’. Recovery level is at 40’. Pump at 450’ in 500’ well. Lowest amperage I saw on cycle sensor was 8.14 amps. Water comes in at 220-280’ and 380-440’.
Ran great a few days. Then the other morning, It was reading r-cycle. Our pressure switch has also tripped to off (gas to be manually reset). Tank is fine with 37-38 psi Precharge. I had rapid cycle time set at 120 sec. have since changed it to 60 sec. I’m not sure what could have caused that. I’ve never seen pump run less than 2 minutes.
Title: Re: Cycle Sensor application
Post by: Cary Austin on September 05, 2020, 06:18:27 PM
The Cycle Sensor is usually telling the truth.  It is watching 27/7/365 and is seeing something you are not.  Maybe the pressure switch it too far from the tank or too much air in the tank is causing the switch to bounce on startup.  Setting at 60 seconds won't make any difference if it is a bounce.  But if it doesn't trip on rapid cycle at 60 seconds, I would move it up to 110 seconds and try again.  If you know the tank takes 2 min 40 seconds to fill when no other water is being used, then it should take at least 2 min 40 seconds every time.  Sometimes the little problems are the hardest to find, but they need to be found.

A 1HP, 5 GPM pump can build 290 PSI.  So pipe would need to be rated for that to work with a CSV or even just to set the pump at 500-600 feet deep.
Title: Re: Cycle Sensor application
Post by: dave4333 on September 12, 2020, 08:07:19 AM
I keep getting rapid cycle lockouts. This morning I turned in a sprinkler zone. I noticed later we had no water. I had turned the rapid cycle time to 60 seconds. Our pump takes 160 seconds to fill tank. Sprinklers definitely ran for a while. No other water was running. I’m wondering if our manual reset pressure switch could be causing the rapid cycle lockout. If the switch gets down to 30 psi and trips to protect pump, could that somehow make cycle sensor think it’s a rapid cycle?
Title: Re: Cycle Sensor application
Post by: Cary Austin on September 14, 2020, 07:54:28 AM
No the lever on the side of the pressure switch will lock out when pressure falls too low.  It won't start back up until you hold the lever up.  Most likely you have a bouncing pressure switch.  You may have too much air in the tank or something?  Have you watched it when switching between two zones?  However, you don't need the low pressure cut off switch when using the Cycle Sensor.  So replacing it with a standard pressure switch would be best.  The Cycle Sensor is telling you there is too much air in the tank, pressure switch is too far from the tank, you have a bad check valve or something.