How to clean the Discharge Check Valve on an ESYBOX MINI 3 to keep the pump from running non-stop. 

Yes. Here's a link. rainwaterequipment.com/search.php?search_query=Y-strainer

Try setting the pressure on your other, larger pressure tank at 15 PSI below the set pressure of the ESYBOX Mini to see if that resolves the looseness and lag in the start time. For more info, you may also review pages 43, 60 and 62 in the manual to see more info on "elastic" and "elasticity". rainwaterequipment.com/content/documentation/E.SYBOX-mini3-manual.pdf

@@rainwaterequipmentllc7835 Thank you very much for your kind comment and my apologies if my English is not the best. I think I didn't explain myself well. What I wanted to say is that with the extra tank, the Esybox works much better, the start and stop demands are much less, result: I am very happy. I had problems with the electronic board at first, but the representative responded immediately by changing the product (it had only been used for a month). Installing a voltage regulator solved the problem. A cordial greeting.

No.

If you have a way to dead head it against a closed valve, try that, and see if it keeps happening. If it stops, then you likely have water dripping or leaking somewhere downstream...or a running toilet. If you don't have a shut-off valve on the pump's discharge, try installing one, and do the test. You may also want to open the priming port just a bit while the pump is running to make sure there's not air trapped inside the pump.

@@rainwaterequipmentllc7835I have the exact same issue as the prior comment. While water is running the Pump will run up to set point and shutoff, drops the RP value, kicks back on gets to set point, runs its time at set point and shuts off. Does this no matter how much flow I run, one faucet in the house on or all of them. Only issue I can see is that while is running or disabled, it is flashing 0.0 gpm. So only thing I can think of is that the internal flow meter has gone bad? Pump hits set point, sees no flow as if all demand has been shut off so it runs for a couple seconds at set point and then shuts off, sees the pressure drop and then starts the cycle again. Any ideas on this would be helpful. I haven’t found any forums addressing this issue.

@@ryanandrews6115 Not sure on this one. Try contacting DAB Tech Support. dabpumps.us/ Contacts link in the footer.

I suppose it’s possible, but a loud noise may indicate that debris may have made its way into the pump if you didn’t have some sort of pre-filter before it. Typically, that’s not necessary though if the water is clean, city water coming in. It’s more common in a rainwater or well water system.

​@@rainwaterequipmentllc7835i realize that the pump gets noisy (creaky noise not normal) after it streams over 18-20lt/min. The water is city clean water.

It sounds like the check valve isn't sealing properly. Please use this video as a guide to check the valve for debris.

Ill give that a go and thanks so much for your prompt reply!​@@rainwaterequipmentllc7835

Do you have a shut off valve installed right after the pump? If not, you should. If so, close the valve, and allow the pump to deadhead the water against a closed valve. If the pump shuts off, there's nothing wrong with the pump. And you either have a leak downstream in your pipe somewhere, or a leaking or running toilet, etc. If not, then yes, try inspecting the check valve (like in the video) for debris.

I have the same problem, I will try to inspect as you said. I will turn back with answer. Thank you!@@rainwaterequipmentllc7835