Roberts Gorden Combat HF 30 v4, Installation, Commissioning, Service & User Instructions

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CABINET HEATER
2.2.3 Sequence of Events
The operating sequence is as follows:
With the external controls on and calling for heat, the burner fan and electric ignition will switch on.
After a combustion air purge of approximately 12 seconds, the oil solenoid valve will open and the burner will fire.
After another 5 seconds the electric ignition is turned off and the burner will go to its normal run position.
The photo cell monitors the safe presence of the flame continuously.
When the temperature control is satisfied, the control box will turn off all its outputs simultaneously, and returns to the
rest position for the beginning of the next sequence.
2.2.4 Fault Conditions
If at any stage during normal running the photo electric cell fails to detect the flame, the control will switch off and make
an instant restart attempt. If the flame signal is still missing “lockout” will occur.
If the flame is not detected by the photo cell during a normal start, there will be no restart attempt and “lockout” will
occur in approximately 17 seconds after the start.
If a flame is detected during the first 12 seconds (purge) the solenoid valve will not open and the control will “lockout”.
For control sequence see Fig. 2.1.
2.3 Control Box - Gas Fired Heaters
(See also the Burner Manufacturer's Instructions)
High /Low and Modulating burners although following the general sequence as described below also have extra functional
stages related to air damper positions. Refer to burner manufacturers instructions for further detail.
Ecoflam gas burner have only one pressure switch which is configured to cover both available combustion air and
reaction to increases in combustion chamber pressure.
2.3.1 Description of Gas Fired Heater Control Box
The gas fired burner fitted to all COMBAT® cabinet heaters is controlled by a full sequence plug-in control box. This
control ensures the safe start and stop sequence and also monitors the safe presence of a flame and burner air
pressure.
The Models 15 to 30 are wired for direct ignition of the main flame. All other models are wired for ignition of a start gas
flame as first stage and then the main gas flame as the second stage.
2.3.2 Sequence of Events
The operating sequence is as follows:
With the external controls on and calling for heat, and the air pressure switch at rest, (contacts n.c. closed), the burner
fan will switch on after a short wait for the control to "self check."
Note: If the air pressure switch contacts (n.c.) are open there will be no start.