Hayward HP50A - Troubleshooting Error Code: E03

36
Verify water is
flowing at pool
return
5. Error Code: E03
Verify the pump
is running
YES
Check skimmer basket
& filter pressure, clean
as needed
Check flow
switch
orientation
Is flow switch
installed
correctly?
After turning
on the pump,
does error
persist?
Error Code:
E03
Shut down
pump, drain
lines &
reinstall
switch
correctly
Problem
solved
NO
YES
NO
If bypass is
open, slowly
close to
determine if
error clears
Did the error
clear while
closing
bypass?
Too much
water was
bypassing the
heat pump
YES
NO
Isolate flow
switch wires &
test for continuity
through switch
with pump
running
Does the
switch have
continuity?
YES
NO
Replace Main PCB:
HPXMCB50
Replace Flow Switch:
HPX20000-360005
Problem
solved