Twice Per Second Flash
(all boards except 6535C320)
Voltage
No Voltage
Check for 120Vac between
“AC1 Black” & “AC1 White”
on the PC Board
Check for 120Vac between
Hot and Neutral on Circuit #1
(make sure hot and neutral
are not switched)
Voltage
Restore proper
power and retest
Cool Mode or Heat Mode?
One of the two wires is bad.
Replace bad wire and retest
Heat
Cool
Remove wires from the
“Indoor Coil Sensor” terminals
and bridge the two terminals
to see if system starts
Start
No Voltage
Run for five minutes in
Electric Heat, then retest in Cool
No Start
Remove wires from the
“Outdoor Coil Sensor” terminals
and bridge the two terminals
to see if system starts
No Start
Run for five minutes in
Cool, then retest in Electric Heat
Replace Coil Sensor
Start
Replace Coil Sensor
No Start
Contact RVP Tech Support
Bridge “F1” & “F2” in the
9-pin plug at the PC Board
to see if system starts
Start
Replace PC Board
!!Shock Hazard Warning!!
T-020 (2-12)
Inspecting electrical components
and systems risks death by
electrocution as well as serious
burns or other injuries to the
inspector or to others.
Do not attempt these tasks unless
you are properly trained and equipped.