Indirect Oil Theory of Operation
When the on/off power switch is turned on, power is sent to a power indicator light on the control panel. Power is also
received by the control board. The control board sends power out to a thermostat “socket”. The socket must have a
“jumper cap” or a remote thermostat plugged into the socket. The heater has a heating element in the fuel filter, the ele-
ment will now receive power from the control board, and begin pre-heating the fuel.
When the thermostat jumper cap is in place, or the remote thermostat is turned up to call for heat, the control board will
begin the start up sequence. During the first step of start up called the purge cycle, the control board powers the motor
and transformer for a short period of approximately ten seconds. The turning motor provides airflow and the transformer
provides spark to light and burn off any residual fuel remaining from prior operation. At this time the fuel solenoid valve
receives no power and remains closed. All fuel pumped is sent back to the fuel tank thru the fuel pump’s return line.
During this purge cycle the photocell which is connected to the control board looks for the presence of flame in the com-
bustion chamber. If flame is detected during the purge cycle, the control board “locks out” or removes power from all
components. The heater is equipped with an air proving switch, air from the turning fan blade must close the switch,
otherwise lock out will occur.
Once the purge cycle is completed successfully, the ignition cycle can begin. The control board now sends power to the
fuel solenoid valve. The valve opens allowing fuel to flow thru to the nozzle. The photocell must now detect flame within
several seconds or the control board will lock out. If flame is detected briefly and then lost, the purge and ignition cycles
are repeated once more and if ignition is not achieved, lock out occurs. Control board removes power to the transformer
a short time after ignition is achieved. If for any reason ignition is lost, the control board will remove power to the fuel
solenoid valve and the purge and ignition cycles will begin. Once ignition is established the thermostat will cycle the
heater on and off as needed.
If lock out occurs the reset button will trip. The heaters need a thirty second wait before the reset will function again.
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Summary of Contents for HVF180
Page 4: ...4 TECHNICIAN ...
Page 5: ... CFM 5 6 ft ...
Page 18: ...Chimney Exhaust Set Up 18 9 ft 30 ft 15 ft 3 ft 12 ft ...
