WINTER MODE
STEP 3
5. Check Z1 (Reset and summer/winter
switch).
Button up – winter mode.
6. Check Z3 (Manual-automatic switch).
Button up – manual mode
Button down – auto mode.
7. Check M2 (Fan thermostat).
The thermostat is closed only when its
temperature
is higher than 104 °F.
TROUBLESHOOTING STEP 3
Point 5 (Z1)
Z1 is open and no ignition block.
Check wirings and connections. If
everything is OK replace the switch.
Point 7 (M2)
M2 is close and fan thermostat temperature
lower than 104 °F.
Check wirings and connections. If they are
OK replace the thermostat.
STEP 4
8. Check Z9 (Room thermostat). Close the
thermostat by a clockwise rotation
9. Check M1 (Overheat thermostat, automatic
reset). The thermostat is closed @ T lower
than 140 °F
10. Check S (Combustion blower motor)
TROUBLESHOOTING STEP 4
Point 8 (Z9).
After a clockwise rotation the contact is still
open. Check wirings and connections. If they
are OK and the room temperature is cold
replace the switch.
Point 9 (M1).
M1 is open and fan thermostat temperature
lower than 140 °F.
Check wirings, connections, gas pressure, fan
motor.
Clean fan blades and air grids
If everything is OK, replace the thermostat.
Manual
Auto
Close @ 104 °F
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