In pool school, under maintenance of sand filters, it says:
What is the purpose of doing the backwash cycle twice? If you want to get it extra clean why not just run backwash a little longer after the water is clear? What is gained by doing
backwash/rinse/backwash/rinse ? What does that extra rinse do?
My understanding is that rinse is just removing water from the filter without the water first going through the sand, while backwash runs water backwards through the sand and then removes it.
What am I missing?
After turning off the pump, move the lever to the "BACKWASH" position and restart the pump. Most multis have a view glass so that you can see the debris coming out of the filter, other filters will have a section of transparent pipe on the backwash line. The water will run clear for a moment, then get dirty, and finally run clear again. When the water in the glass is ~ clear, turn off the pump. If you have a multiport valve with a "RINSE" setting, switch the multiport to "RINSE", otherwise switch to "FILTER", and run the pump for about 15 seconds. Repeat the backwash cycle.
What is the purpose of doing the backwash cycle twice? If you want to get it extra clean why not just run backwash a little longer after the water is clear? What is gained by doing
backwash/rinse/backwash/rinse ? What does that extra rinse do?
My understanding is that rinse is just removing water from the filter without the water first going through the sand, while backwash runs water backwards through the sand and then removes it.
What am I missing?