Hayward HC Series User Manual

14. Service LED ON: “A1, A2, & A3” Code
“A1” Code stands for “Air switch circuit open before ignitor warm up”. Differential Pressure Switch (DPS) open
when expected closed. The switch circuit never closed when the blower turned on or re-opened within 10
seconds of blower starting.
“A2” Code stands for “Air switch open after ignitor warm up”. Differential Pressure Switch (DPS) open when
expected closed. The switch opened during the heating cycle.
“A3” Code stands for “Air switch open during post purge”. Differential Pressure Switch (DPS) open when
expected closed. The switch opened after heating cycle ended but before the post purge time (30 sec.)
completed.
51

Hayward HC Series Specifications

General

Brand	Hayward
Model	HC Series
Category	Heater
Language	English