The general rule is to backwash when the PSI rises 7-10 points above normal operating pressure (the pressure the filter runs in high speed following a filter clean in pool mode: the filter pressure will always be higher in spa mode. This is called “native” pressure), or every 3-4 weeks.

Some pressure gauges do not register large changes in pressure and some filters need to be backwashed more often.

 

Why This Is Important: It’s important to keep the pump circulating and filtrating at maximum efficiency. Also, with high PSI over an extended period of time, it can cause damage to the filter and pumps.