Iron filter backwash causes pressure drop

[cobretti]

Hi All,

Hoping for some advice with this issue - i found this thread with related terms but i don't have exactly the same issue - https://terrylove.com/forums/index....ng-system-running-well-dry.76765/#post-562427.

Basically we moved into this house with everything in a completely unmaintained and/or near broken state. We moved from suburb to rural so this was all new to us but I managed to replace everything I could myself. All was working ok until I added this iron filter

http://store.afwfilters.com/iron-su...ction-systems/air-injection-silver-20-system/

My problem is that whenever the iron filter kicks in for its backwash cycle it seems to do it faster than the pressure tank/well can handle it so my pressure will drop to 0 within 5-10 minutes of the hour long cycle. If I select the button to go to next stage and hold the pressure switch till it gets to 40 it will go to 60 as usual but then there is another 10 minute rapid rinse at the 3rd stage and that will again use all the water before the stage completes. I can then after that manually engage the switch again and tank will fill and we are good until next time the filter backwashes. I even extended it to every 3 days but then my wife will always remind me very nicely "no water again!"

It's a 50G tank set at 40/60 and unfortunately I do not know what pump is in the well. Is there anything I can do to help the system cope with this filter in place. Would adding a second pressure tank in series help?

Thanks you for any advice!

 

[Reach4]

So is it the level of the water in the well dropping, or is it the pump not keeping up? I think it is the level of the well dropping. If it were the pump not keeping up, the pressure would settle at some amount, and stay there during the backwash or rapid rinse. A bigger pressure tank is not likely to help.

I don't know the cycles in your system. Maybe you could just shorten them up... backwash to 5 or 6 minutes, and similar for the rapid rinse.... What are all of the cycles and the current settings?

How many GPM does your backwash take? You might have a talk on the topic with your dealer.

If you want confirmation, get a clamp-around ammeter. If running out of water, the amps will drop. If the pump cannot keep up with demand, then the amps will stay high.

You could get a system where the submersible fills an atmospheric tank, and a separate pressure pump provides pressure to the house.


I am not a pro.

 

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[Valveman]

Pressure tanks are completely empty before the pump comes on, so a larger or extra tank won't help. I don't think the well is being depleted as it picks right back up and goes to 60. My guess is the back wash is using more water than the pump can produce. If it is back washing successfully at the low pressure, just get a regular pressure switch and do away with the low pressure cut off pressure switch. If you want Dry Well protection use something like a Cycle Sensor that looks at amps instead, and won't go off because of low pressure.

If the low pressure is not back washing properly, you will need to figure out how many GPM's are needed for what length of time. If it isn't too much different than what the pump can make, you maybe able to use a lower air charge in the pressure tank to supply the extra volume. If there is a big difference, you will need a larger pump just for the back wash.

 

[cobretti]

Thank you very much guys - will check all these tonight after work. I did contact the iron filter dealer and they said I need minimum 6gpm and according to well info it is supposed to produce 10gpm but that data looked very old. he said to reduce time as well for backwash but I can only go down to 8 minutes and as noted by the time 5 minutes has passed it empties the tank.

 

[Reach4]

Just thinking here... suppose you had a device that shut down the pump after you run out of water. Let's say you want at least 10 minutes of backwash Lets say you set that device to shut you down for 5 minutes each time you run out of water. After that, suppose the well is ready for another 3 minutes of backwash. So you set the backwash to 21 minutes. Then expect 5+ 3+3= 11 minutes of backwash.

Just an idea. Cycle Sensor is such a device.

What size is your well casing? It is possible that you could lower the pump and get more available water stored. The downside is that you could start pumping up more sediment.

There are also techniques to increase the yield on wells.