Tuesday, 22 July 2014

How to backwash a sand pool filter [side valve]

The popular belief is that pool filters need to be replaced once they stop performing to expectations. The point is pool filters are often costly especially when associated with fitting costs and accessories. Often a simple backwash can restore the performance back to you pool filter. So why not back wash the pool filter and breathe life back into it? This will save you a couple of hundred bucks for sure.

The following steps should guide you to backwash a sand pool filter with a side valve.

How to Backwash sand filter with slide valve:

1. If you have a backwash hose roll it out and shut down the motor.

2. Pull the plunger T-handle upwards 2-3 inches so that it is unlocked.

3. After opening the air bleeder assembly you then turn the pool pump on.

4. Check the pressure on the pressure gauge, to verify the hose has no kinks.  This should be +40 PSI.

5. When water is running clear through the hose you can shut off motor.

6. Return the T-handle to the locked position by pushing down.

7. Turn the pump back on and roll up the backwash hose and you are finished.

Your filter should run for 4 weeks at least before you need to backwash it.  There is a problem with the filter size or sand in the filter if you need to backwash in less time.

Sand pool filters are constituted of a special grade #20 silica sand that is capable of sieving out contaminants and dust particles in the size range of 20 to 100 microns. The irony is that the sand filters tend to have increased efficiency as they collect more and more dirt. This could be attributed to the increase in density of the sand as more dirt gets collected in it. Just like other filters sand pool filters would not continue performing after a period ad you’ve got to backwash them to restore performance.

When the pool pressure gauge shows a reading of 8-10 lbs over it’s initial reading, it’s time to back wash the sand pool filter.

Backwash sand filter that has a multiport valve?

1. Pool Motor has to be shut down.

2. Move the valve setting from FILTER to BACKWASH by depressing the valve handle.

3. Open all the waste line valves and roll out backwash hose.

4. Turn pool pump on AFTER opening the air bleed assembly on the filter.

5. Verify the hose has no kinks, checking the pressure gauge for backpressure.

6. Run the pump motor for 2 to 3 minutes so that the water runs clear.

7. Now move the multiport valve handle to RINSE for 15-30 seconds.  This is AFTER you turn off the motor.

8. Shutting off the motor, now move the multiport valve handle to FILTER.

9. Finally turn the pump back on checking for a lower pressure reading and then roll up the backwash hose.

If you’re not using a sand pool filter that has a multiport valve, you can refer to the post on how to backwash a sand filter with slide valve.