dunphy TAD4 Operating Manual Download

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Operating Instructions For TD/TAD4 Dual Fuel Burner

June 13 72 of 165 TD/TAD4 Manual Rev 4

7.4.7

Adjustment of Gas Proving Pressure Switch

Loosen the screw in the gas inlet measuring point, connect a manometer and remove the clear
plastic cover from the gas pressure detector.
Switch on the burner and allow to fire.
Close the burner manual gas isolation valve slowly until the gas pressure is reduced to 50%.
Adjust the numbered black plastic ring on the gas pressure detector until the burner switches off.
Switch off the mains electrical supply to the burner, remove the manometer and seal the test point
screw.
Open the manual gas isolation valve and switch on the burner.

7.5

Oil Firing

All burners using oil as a fuel are fired before despatch as part of the standard test programme. This
does  not  mean  that  the  pump  pressure  or  any  other  adjustment  applying  to  the  oil  system  is
necessarily correct for the application.

Commissioning of the burner must include confirming that the nozzle size and characteristics are
suitable, calculating the  fuel  pressure required to  give boiler M.C.R. and  ensuring that, subject  to
the requirements given below, the firing rate is correctly set.

The following text in included on the basis that the burner has been commissioned on gas and that
the boiler or appliance controls have been set.

The change - over of fuels is made by operation of the selector switch on the burner control cabinet.
This selector switch controls two contactors which electrically isolate one fuel from the other. On
electronic modulating burners, fuel selection can be made via the keypad.

For change-over to either fuel the switch selection is made through the 'off' position which causes
the burner control box to extinguish the flame before recycling.

The  starting  cycle  will  not  immediately  commence  because  it  will  be  necessary  for  the  burner
motor to slow down, reducing the air flow to a level which allows the air pressure switch to return
to the 'no' air position.

Note: Even on oil firing the leak detection cycle will be activated.

Before changing to oil firing, ensure that the oil pump has been properly vented and flooded.

No mechanical changes or re-adjustment of components are required for the burner to be changed
from one fuel to another.
Before the first firing on oil, it is always advisable for the availability of fuel, fire valves open etc,
to be confirmed.

Check that the burner will remain at low fire.

7.5.1

Setting the Firing Rate, High / Low Oil Burners

Step 1



Set the Low Fire air damper motor setting to between 1 and 2 on the scale and the high fire
air damper setting to between 5 and 6 on the scale. Set O2 to approx 3 on the scale.



Ensure that the High / Low switch is in the low fire position and switch on the burner.



Momentarily 'blip' the oil pump contactor to check for correct rotation of pump - ensure it
rotates according to rotation sticker fixed to rear of the motor. If rotation is incorrect, swap