CenCon
35
M-XM
For direct fired HE style direct fired heaters.
BASIC OPERATION
On a call for heating, and with the supply blower enabled, the ignition control will be enabled to start and
prove pilot flame, then open the main safety valve (SSOV). Once the pilot flame has proven and the main
flame is established, the M-XM will then disable the pilot valve. The burner is allowed to operate to maintain
the requested discharge air temperature from the CenCon by modulating the control valve. If heating is not
required the burner will be disabled, and then shut down.
M-XM / P-XM TIMING
Flame failure alarm
15 seconds lockout on ignition control
60 seconds on burner
Pilot opening time
10 seconds
Mode change time
60 seconds
Damper delay off
20 seconds
Improper gas valve wiring alarm
2 seconds
Supply air low airflow alarm
30 seconds
Shorted damper end switch alarm
1 second
Supply air shorted air switch alarm 30 seconds