MGN 2800N HP 20
High Gas Pressure Switch Setting
When the burner is finally commissioned the gas switch must be adjusted with the burner running.
Remove the cover, and move the dial in an anticlockwise direction until the switch trips and the
pressure switch indicating light is illuminated (the burner will shut down). Move the pressure switch
dial in a clockwise direction one division, fit the cover, and reset the pressure switch via the button
situated on the pressure switch cover. The burner will now restart.
Low Gas Pressure Switch Setting
The low gas pressure switch is wired in series with the appliance controlling instruments and will
cause the burner to effect a ‘safety shutdown’ if a loss in inlet gas pressure is detected.
Isolate the burner and remove the gas pressure switch cover. Switch on the electrical supply and
allow the burner to establish main flame. Slowly turn the adjustment dial on the gas pressure switch
clockwise until the flame is extinguished and the burner shuts down. Turn the dial slowly
anticlockwise one division at a time until the burner restarts and establishes main flame. Re-check
the performance and then turn the dial a further two divisions anticlockwise. Switch off the burner
and replace the gas pressure switch cover.
FINAL CHECK
Check that all covers to components have been replaced and that locking devices are properly
secured. Check that the appliance control instruments are set to safe limits.
Commissioning is now Complete
Switch on the electrical supply.
The burner will now operate until switched off:
a. by controlling instruments of the appliance
b. manually
c. by power failure. On restoration of power, the burner will restart automatically and follow
sequence.
RWF 40 MODULATING CONTROL
Basic Display
The diagram opposite shows the RWF40 after switching on the supply voltage. This condition is
called the basic display. The actual operating value and the currently active set-point will be shown.
Manual operation, self-optimisation, the operating parameter and the configuration levels can be
activated from this display.
To change the working set point
The basic display shows the actual pressure/temperature of the boiler in red and the required set
point pressure/temperature beneath in smaller green digits.
One quick press of the PGM button, the display changes to show the set point as the larger red digits
and the SPI in the lower small green digits.
Alter the red display using the up/down buttons to show the new required set point, press exit or let
the unit time out to return to the basic display which should be the new set point figure.
To enter a new parameter
The parameters dictate the way in which the burner firing rate alters in response to changes in the
pressure/temperature of the boiler.
A major factor that determines the need to change the parameters is if the burner is fitted to a steam
or hot water boiler. The table below indicates the parameter and its setting for steam and hot water
boilers. it must be emphasised that it is only an indication and any departure from these settings
should be made in small increments, with time given to see how the burner is reacting to the changed
parameter.
