How do I clean my water well's filter and how often?

Question

What is the procedure for periodically flushing (to clean) this filter (shown)?

I open red valve for a couple seconds. But how to do I flush out the junk that I can see in the filter? Filter uses a series of small mesh, little metal screens.

And how often?

I've had tiny black grit in watering landscape valves, probably from the well.
When I dump the red valve at bottom of filter, after a couple three weeks, blackness comes out for a split second, then all clear.

I'm on 5 acres in northern California and we are on wonderful well water for the first time, watering a lawn, garden, and fruit trees.

Supply from pressure tank is on right; left goes to house & property.

Answer 1

Flushing is fine for what it does. Your filter is evidently installed backwards, as the flow arrows show correct flow from left to right, but you say flow is right to left. However, it looks like the pressure tank is to the left, so...? I use one of these "spin-down filters" with 200 mesh stainless steel screen myself, but it's installed in the right direction.

If you wish to clean it more, or (if you are having grit get through it) replace with a finer filter screen, shut off the water on both sides and unscrew the whole clear canister, after releasing pressure with the bottom valve. Someone has complicated that by attaching electrical conduit as a hose (seriously janky) to the bottom valve, which you'll have to remove to remove the clear canister. If it's the same maker as mine, the stainless screens only go to 200 mesh, but polyester screens are available up to 1000 mesh. You can add a different type of filter after this if you have material getting through that's too fine even for that.

Due to physics, it will also work a lot better if the flow is the correct direction, as it's supposed to "throw" heavier stuff out of the water stream by centrifugal action, when flowing the right way. And the flush valve is probably not flushing the collected junk on the screen very well, as the collected junk that hasn't passed through the screen will be on the wrong side of the screen, if it is indeed backwards, as it appears to be.

If the place it is is not in full darkness except when you are working on the pump, it's advisable to put an opaque cover over the canister to prevent algae growth. How often to flush it depends on how fast it fills with crud.

There's no schedule that isn't directly affected by "what does your well cough up to clog it with" and that's going to be unique to your well. For some wells, it also changes by season of the year. You can get a related but different version with a larger area for crud to collect between flushings, below the filter section.

Answer 2

Close the black valve and then open the red valve.

water from any pressure tanks or hammer arrestors downstream will flow backwards into the outlet and then out of the bottom of the bulb washing the filter element.

Then the open the black valve to flush the dirty water out of the bulb, and close the red valve to return the system to operation.

Answer 3

That looks like a simple screen filter that you don’t clean you just dump the sediment by opening the ball valve and let it flow long enough for the sand to be discharged (exactly what you have been doing) usually the mesh is brass and lasts forever unless plugged up. This type has the lowest pressure drop but only filters the larger particulates, I like string filters because they filter the fine grit that is giving you problems,

String filters are changed not cleaned, some change them at a large pressure drop others change them monthly but a string filter will eliminate the fine grit getting through.