Can I fix Pentair code ERR PS myself?

Start with these safe checks: Make sure the pump is running and, on a variable-speed pump, at a high enough speed. Turn the pump off at the breaker, then empty the skimmer and pump baskets and clean the filter (release filter pressure first). Check that valves to the heater are open and the water level is mid-skimmer. Pentair warns never to bypass the pressure switch. If flow is good and the code stays, have a qualified tech test the switch.

When should I call a technician for code ERR PS?

Pentair warns never to bypass the pressure switch. If flow is good and the code stays, have a qualified tech test the switch. Smell gas? Leave right away, don't touch light switches or phones inside, and call your gas utility or 911 from outside. Never open a gas valve, burner, gas line, vent or flue connection, or bypass a safety switch. Repeated lockouts, scorching, soot, or a CO alarm mean shut it off and call a licensed gas technician.

Pentair Pool Heater Error Code ERR PS / PS: Water pressure switch…

What ERR PS means

The water pressure switch is open because there's no water flow through the heater. It clears once flow is established.

Also shown as: PS, depending on the model.

Likely causes

Pump off or set too slow
Dirty filter
Full skimmer or pump basket
Closed or misset valves
Low pool water

Safe first checks

Make sure the pump is running and, on a variable-speed pump, at a high enough speed.
Turn the pump off at the breaker, then empty the skimmer and pump baskets and clean the filter (release filter pressure first).
Check that valves to the heater are open and the water level is mid-skimmer.

When to stop

Pentair warns never to bypass the pressure switch. If flow is good and the code stays, have a qualified tech test the switch.

Parts that may help

Only order a part once the checks above point to it, and match the part number to your model.

Pressure Switch - Adjustable, SPST-NO, 4010P$36.99

Checked against: Pentair MasterTemp heater installation and user's guide (Table 8: error and fault codes). Codes can differ by model and year, so confirm with your owner's manual.