Check the power across the green
and white wires of the yellow control
cord. Is there 24V power?
Is the power across the 24V terminal and
the ground on the circuit board 24V?
Does the fan
blower turn on?
Is the power across the TH terminal
and ground on the circuit board 24V?
Is there 120V on the
primary side of the
internal transformer?
Is the power at
the heater 120V?
Find the source
of the electrical
problem between
panel and heater.
Does the ignitor
warm up and
glow red?
14
4.0
Troubleshooting Guide
4.0
Troubleshooting Guide
Turn up thermostat
No
Yes
Continued on page 16.
AG2
Series
Yes
No
No
Yes
No
The circuit board
is faulty and must
be replaced.
No
The internal
transformer is
faulty and must
be replaced.
Yes
Yes
No
The relay board is faulty
and must be replaced.
Yes
Is the LED flashing a fault code?
(See page 13 for code status, then
continue troubleshooting below.)
Is the circuit board
sending 120V to the fan?
No
Yes
Is the blower obstructed?
The blower
is faulty and must
be replaced.
No
Yes
Remove obstruction.
Yes
