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

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CABINET HEATER
For Ecoflam High/Low or Modulating burners then the Dungs gas valve has extra features as it is an air/gas ratio
control valve.Please refer to the manufacturers instructions regarding the setting of these controls.
The design of the gas train circuits is shown in Fig 2.5.
Orifice Plate
Most models require the fitting of a restrictor (orifice) plate between the main gas valve outlet and the burner to prevent
the burner from being over fired and provide suitable operating conditions for the gas valves.
Orifice Plate Position
Ecoflam Burner
For all models this will be fitted into the special union between the main valve and the burner at the point where the gas
supply enters the heater.
2.7.1.1 Start Gas Valves
For models PGP015 to PGP030 there is no start gas valve fitted.
For all other models the start gas train is fitted with a pressure regulator and two start gas safety shut off valves.
The start gas regulator is used to adjust the burner firing rate during the start gas phase of these models.
2.7.1.2 Main Gas Valves
Figure 2.6 shows the position of the burner pressure regulation adjustment. This must be used to set the burner
pressure as in the Data Tables as described in Section 5.
Note: For Ecoflam High/Low or Modulating burners then the Dungs gas valve has extra features as it is an air/gas
ratio control valve.Please refer to the manufacturers instructions regarding the setting of these controls.
2.7.1.3 Throughput Adjuster
Fig 2.6 shows that these types of valve have a throughput adjuster fitted to the second main gas valve.
This will be factory set at fully open on new appliances and will need no further adjustment.
When replacing a gas valve ensure that this device is set in the fully open position by releasing the locking screw and
turning the ’V MAX” fully counter clockwise towards the " + " sign and then re-tightening the locking screw.
2.7.1.4 Rate of Opening
Fig. 2.6 also shows a slow opening adjustment. This device is a hydraulic damper which slows down the rate of
opening of the second main gas valve to give a smooth main gas ignition.
This is preset at the factory at the slowest setting and will need no further adjustment.
If a new valve is fitted than remove the plastic screw-on cap and with a small screw driver turn the “V start” screw fully
clockwise towards the " - " sign. Refit the plastic cover.