The main burner pressure should be checked dur- ing commissioning to make sure the correct input is obtained. Proceed as follows: •Shut down boiler. •Undo screw on burner pressure test point below sealed combustion chamber,

COMMISSIONING

On reaching maximum temperature, the boilershould be turned off and the system drained as rapidly as possible whilst still hot. •Refill system to a pressure of 1 bar and vent as before. •Restart boiler and operate until a maximum tem- perature is reached. Shut down boiler and vent heating system. If necessary, top up heating sys- tem and make sure that a pressure of 1 bar is indicated on the pressure gauge when system is COLD.
Diagram 23 Des 044 Diagram 24 Reg 056 ° C. When the temperature reaches16 ° C, the boiler stops. Note: This device works irrespective of any roomthermostat setting and only protects the boiler. •Remove screw from inlet test point on the side ofthe gas valve, THEMA F 23 E boiler has a built in frost protec-tion device that protects the boiler from freezing. If the boiler is to be left and there is a risk of frost, ensure that the gas and electrical supplies are left connected and the summer/winter switch is in theposition. The frost protection device will light the boiler when the temperature of the boiler wa- ter falls below 6 Important notice: A central heating system cannotoperate satisfactorily unless it is properly filled with water and unless the air initially contained in the piping systems has been properly bled off. If these conditions are not satisfied, air noise will occur within the system.The

SAFETY DEVICES

Air flow rate safety device If an obstruction, even partial, of the flue occurs, for any reason whatsoever, the built in safety sys- tem of the boiler will turn the boiler OFF and the fan will continue to run. The boiler will be ready to operate when the fault has been cleared. In case of power supply failure The boiler no longer operates. As soon as power supply is restored, the boiler will be automatically restarted. Overheat safety In the event of a problem, the overheat thermos- tat causes safety shutdown of the boiler. Should this occur, reset the thermostat by pressing in the red button. The overheat thermostat is located on the RHS of the heat exchanger. 16