Drip Irrigation Causing Cycle Sensor to go into RCYC mode?

[Lou N]

All,

A couple of moths ago we installed drip irrigation in the garden. It runs for 20 minutes early in the morning restricted to 15 psi; no issues until recently the Cycle Sensor has been shutting down the pump showing it's tripped due to short cycling (RCYC mode). Could the drip irrigation cause this?

We had the well pump replaced 3 years ago; it has been relatively dry, but we just had a good rain two days ago and the pump was off this morning again.

I did check the pressure tank the other day and re-confirmed it was holding pressure (38 psi on a 40/60 pressure switch).

Could the drip irrigation be pulling down the well level too far? (the pump is at 133' and when they replaced the pump it was showing 30' of water in the well).

No air in the system, just going into RCYC mode. When the pump runs from zero pressure the max current is approx 4.5A.

Thanks,
Lou

[Cary Austin]

You didn't say if you also have a Cycle Stop Valve on the pump?  If so, the drip is probably using less than 1 GPM , which causes the CSV to let the pump cycle.  If you do not have a CSV on the pump, it will certainly cycle with drip running.  What causes the RCYC fault is when the pump comes on and doesn't run as long as you have the Rapid Cycle feature of the Cycle Sensor set for.  If the Rapid Cycle feature is set at 60, the pump must run 60 seconds every time it comes on or it will trip on RCYC.  You can lower the Rapid Cycle number, but it is usually telling you something else is wrong.

[Lou N]

Cary,

Thanks for the reply. I do not have a Cycle Stop Valve on the pump, just the sensor. Yesterday I changed the time for the drip to run to 11:30 PM, for 20 minutes. This morning at 0500 AM the sensor was reading RCYC again; and there was air in the faucets.

I should also mention the we have water softener system that is set to run at 0200 AM.

Up until the recent dry weather we had no issues, so I'm wondering if the drip system could be drawing the well down too low due to lack of rain and causing issues, including the air in the system?

I checked and the settings for the Cycle Sensor are: Current Adj -3.65A, Dry Run Delay - 25 minutes, Rapid Cycle Setting - 45 seconds

I'll turn the drip off today and see if the problem repeats itself tomorrow. I guess I can also try lowering the Rapid Cycle number, but other than that I guess I'll have to call the well company back out.

Lou

[Cary Austin]

The Cycle Sensor is telling you something.  If you lower the "current adjust" number it may not go off when the well pumps dry.  Best to test for that number before lowing the setting of the Cycle Sensor.  I would not think drip would cause a low well condition, as it is usually only like 1-3 GPM.  But I guess it could be a big drip system that uses as much water as sprinklers.  Which, BTW, without a CSV the sprinklers or drip should be set to max flow to keep the pump from cycling on and off.  But if the systems cycles when the drip is on, it is not a large enough flow rate to keep the pump running as it should.  But that also should not be maxing out the well.

Run a back flush on the filters or just turn on enough drip to MAKE the well pump dry.  Not the numbers on the display of the Cycle Sensor before the pump is shut off and says DRY.  It will only stay at this number for 10 seconds, so keep an eye on it.  Whatever that number is before the Cycle Sensor says dry is how low the amps will go on that pump/motor.  You can set the Cycle Sensor slightly higher than that number ands still be safe from running the pump dry.

If it is pumping the well dry you can just space out the irrigation more and run for fewer minutes at a time.  Air in the lines is a pretty good clue the well is really being pumped dry and the Cycle Sensor is doing its job..

[Lou N]

Cary,

Ok I'll run the test as suggested.

This afternoon I placed a garden hose in the pool and ran it for twenty minutes. The system worked fine, never went into RCYC/DRY mode. The maximum current was 4A when the pump kicked on and just about 3.95A just before it kicked off (I did notice a very brief spike of approx 25A when the sensor flashed RUN, just a flash, only one time).

On average it took about 2 minutes to draw down the 36 gallon pressure tank; the fill time varied between 2- 4 minutes. No air in the system, no issues.

We'll see what happens tonight with the drip turned off.

BTW the drip manufacturer recommends a 15 PSI restrictor on the output side of the feed, not sure if that's contributing to the issue.

I'm having issues logging into the forum, so my responses may be delayed. I appreciate your time and advice.

Lou

[Cary Austin]

A high peak amp draw on start up is normal.  The 15 PSI regulator is common and not important.  What is important is the GPM of the drip system zones.  Are the zones larger than the output of the well is the question.

A Cycle Stop Valve would help as 2-4 minutes between cycles is a lot of cycling, which will destroy the pump, tank, switch, check valve, and other things. 

[Lou N]

Cary,

I don't believe that the output from the drip system would exceed the well capacity. We're using 5/8" tubing with drip emitters, not an actual sprinkler type system. I turned off the drip system last night and this morning there were no issues, so it appears that it is related to the drip system.

I'm looking over the website to see what would work for ourt application, that is, just a cycle stop valve with our older existing pressure tank, or a complete pressure tank/CSV kit.

I was eventually going to replace the 36 gallon pressure tank, but it's hanging in there. I'm attaching a couple of pictures of the current plumbing setup. If you could recommend which CSV I would need, and if I went with a full system which Side Kick kit.

Thanks,
Lou

[Cary Austin]

You need to add up the drip emitters and see how many gallons per hour you have and translate to gallons per minute.  My guess is you are not even using 1 GPM, which is 60 GPH.  IN that case the 45 seconds you have set in the Cycle Sensor for rapid cycle fault it too much. With no other water running the tank fills faster than when a faucet, shower, or other device is using some water.  Just turn down the rapid cycle setting to say,35 seconds until you get the Cycle Stop Valve installed.  With the CSV installed you can make it take as long as 8 minutes to fill the tank and shut off. 

The 32 gallon size tank only holds 8 gallons of water.  The 10-12 GPM pump is filling the 8 gallons in the tank too fast, and causing the Cycle Sensor to detect a short run time and shut the pump off.  The CSV will only fill the tank after all water uses are turned off, and then it will only fill the tank at 1 GPM.  To get about a 2 minute run time to fill the tank as needed, we just set the CSV1A for 55 PSI to work with your 40/60 switch.  In this way the CSV gives 55 PSI constant, and only takes 2 minutes to fill the tank after water use stops.

Just cut that 1" PVC pipe right where you made the red arrow that says "from well".  Screw a couple of 1" PVC male adapters to the CSV1A and glue it in that place.  Order it preset for 55 PSI and your done.  Or set it yourself to 55 PSI with a shower running.  You will like that strong constant 55 PSI when you are done.

Oh yeah, then reset the rapid cycle feature in the Cycle Sensor for about 90 seconds because the rapid cycle problem will have gone away as well.

[Lou N]

Cary,

Thanks again for the detailed reply. I will see if I can figure out the gpm for the drip emitters. In the meantime, I'll set the rapid cycle sensor to 35 seconds and get a CSV1A ordered. BTW if in the future when the pressure tank needs replacing which of the I purchase the pressure tank kits would I need?

Regards,
Lou

[Lou N]

Cary,
The plumbing that runs to the well head is 3/4" sch 40 PVC I assume that it will be able to handle the expected back pressure from the CSV?

Lou

[Cary Austin]

3/4 sch 40 pipe has an operating pressure of 289 PSI and a burst pressure at least twice that much.  Your 1/2HP pump will only be able to make about 100 PSI back pressure.

[Lou N]

Perfect, thanks.