How do I backwash my sanddollar pool filter - Pentair Sand Dollar 19" Filter with 1 Hp Dynamo Pump System Fil Pen 145148

COULD BE TOO MUCH CHLORINE.

FILTER is the valve position when the system is in the normal filtering mode.
When you backwash the filter you first need to turn off the pump, place in BACKWASH position, and run the motor for 45 seconds (or until the backwash water is clear). Turn off pump and run in the FILTER position for 15 seconds. Repeat twice more.
The RINSE position is to clear any dirt in initial start-up cleaning, plus resetting filter bed after backwashing.
The WASTE position is for vacuuming directly to waste, lowering pool level, or draining the pool.
The CLOSED position is for shutting off all flow through the valve.
The RECIRCULATE position allows water to flow from the pump through the valve and directly to the pool.

You will probably only to use the FILTER, BACKWASH and maybe the RINSE valve position. The RINSE position is not as important as indicated by the fact that many backwash valves don't have a RINSE position.

I hope this helps.

b> VALVE SETTING FUNCTIONS OF VALVE POSITIONS FLOW DIRECTION THROUGH VALVE FILTER PUMP - TOP - THROUGH FILTER - BOTTOM - RETURN For normal filtration and vacuuming pool through filter. BACKWASH b> PUMP - BOTTOM - THROUGH FILTER - TOP - WASTE For reversing flow for cleaning filter. RINSE b> PUMP - TOP - THROUGH FILTER - BOTTOM - WASTE For initial start-up cleaning, plus resetting filter bed after backwashing. WASTE b> PUMP - WASTE For vacuuming directly to waste, lowering pool level/draining pool. CLOSED b> NO CIRCULATION PAST PUMP PORT For shutting off all flow to filter and pool. RECIRCULATE b> PUMP - RETURN For bypassing filter, but circulating pool water. May be plumbed for "off-system" pool water access. Ideal for Jet-Air® fittings. WINTER b> VALVE NOT IN USE
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After your pool filters on the "backwash" setting, you should move it to the "rinse" setting. With the pump off, set valve to rinse. Start pump and operate for about 1/2 to 1 minute. This ensures that all dirty water from backwashing is rinsed out of the filter to waste, preventing possible return to the pool. Stop pump, set valve to "filter", and start pump for normal filtering. If it still won't start, check for restrictions in the intake and discharge lines.

To Flush out the filter with the backwash setting. The backwash setting releases trapped particles from the filter back into the swimming pool. You may need to alternate between the rinse and backwash settings until the water runs clear in order to unblock your filtration system and flush out clogs. To Rinse away dislodged items from the backwash setting. The rinse setting flushes clean water through the pipes and carries away any particles or clogs freed during the backwashing. To Drain the pool select waste on the multiport valve. This sends the water directly to the drain rather than back into the swimming pool. Close the filtration equipment and stop the pump with the closed setting. You should only use the closed setting when you turn the pump off. This function allows you to remove the strainer basket, clean the filter tank and perform other swimming pool maintenance on the filtration system.

After you have backwashed your filter until the site glass run clear. Go to rinse mode for 30 seconds. Make note of the filter pressure. Don't backwash until the pressure goes up 10 psi!! It is important not to backwash too much. As pressure climbs the sand filter actually filters better.

backwash the filter from main drain until sight glass is clear-this will reduce filter pressure. After backwashing return gate valve to filter position, then filter from main drain only. check water chemistry. add a clarifier to water

water level must be about the discharge (eyeball) in the pool to back wash. Check the hose connections to make sure that hoses off the the filer head are going to the right place Look for the words "Pump" , "pool" and "waste" molded into the valve. I've seen it a number of times where "Pump" and "pool" were connected the wrong way.