Filter Pressure Gauge

How do you read the pressure gauge?

Hi. The pressure gauge on an above ground pool filter is used to determine the amount of water flow going back into the pool. This lets you know when the filter media needs cleaned.

The instruction manual for a sand filter will tell you to backwash the system before using it for the first time. This will clean out any dust that might be in the sand and avoid getting any of into your clean, fresh pool water. After your initial backwash and rinse you can then go to the filter position. You would at this time check your pressure gauge. This will be your clean operating pressure and when the gauge goes up ten pounds then you should backwash again.

A typical reading might be 8 lbs at clean pressure so you would backwash at 18lbs. That is, of course, if the pressure gauge is working correctly. They tend to freeze up and need replace on a regular basis so it may be possible your gauge is not telling you a thing.

I have never replaced a bad pressure gauge because I do not use them. The water coming out of the return fitting, back into the pool, tells me everything I need to know about my filter operation.

If I have a strong flow of water the filter is fine. If the flow is weak the media needs cleaned. This applies to all types of filters. A sand filter needs backwashed and a cartridge filter needs the element hosed off. If the return flow is full of air bubbles then I know to look for an air leak on the suction side of the pump. The usual cause of this would be air getting in under the hair and lint pot lid.