Principles Of Operation; Component Description - Proheat M50 G-II PCM Service Manual

2.0 PRINCIPLE OF
OPERATION
2.1 COMPONENT DESCRIPTIONS
Combustion Air Blower:
Impeller-style blower driven by the Motor provides the principle combustion air.
Motor:
Drives the Combustion Air Blower, Air Compressor and Fuel Supply Pump.
Fuel Supply Pump:
A positive displacement, gear-type pump that draws fuel from the vehicle fuel
tank and supplies it to the Fuel Regulator. Pressure is regulated between
5 – 10 PSI by means of an internal relief valve. Fuel is re-circulated within the
pump, therefore a fuel return line to the tank is not required.
Fuel Regulator:
Diaphragm-type pressure reducing valve. The Fuel Regulator drops the fuel
supply pressure to atmospheric pressure (0 PSI).
Fuel Nozzle:
Air-aspirating type burner nozzle. Compressed air flows through the air
passages, exiting the nozzle in front of the fuel orifice creating a vacuum in
the fuel supply. This draws fuel from the Fuel Regulator and the combined
fuel/air mixture is atomized into the combustion chamber.
Fuel Solenoid Valve:
Electrically operated solenoid valve which controls fuel flow to the Fuel Nozzle.
Air Compressor:
Diaphragm compressor that supplies air pressure to the Fuel Nozzle.
Note that older versions of M-Series use a rotary vane compressor. Refer to
page D-1 for more information.
Ignition Module:
Electronic Ignition Module with plug-in electrode.
G-II PCM:
Electronic control module that monitors inputs from the sensors and controls
(PROHEAT Control Module)
outputs to PROHEAT components. It has an integrated Flame Sensor that photo-
electrically measures the intensity of the flame to determine if a flame is present.
Also built-in to the G-II PCM is a Status Indicator Light that shows operation,
function/component problems and CANbus connectivity to assist with trouble-
shooting. Operation and fault history can be downloaded and viewed on a
computer using PROHEAT Data Link software.
Note that the older G-I PCM version does not have a built-in Status Indicator Light.
Refer to page C-1 for more information.
Combustion Tube:
Directs the air supplied by the combustion air blower through a swirler into the
combustion zone, mixing it with the atomized fuel/air mixture from the Fuel Nozzle.
PROHEAT M-SERIES G-II PCM SERVICE MANUAL 2-1