Main Heating Main Heat 12, Installation & Service Manual

Page: 46 / 83

Fig. 25 & Fig. 25a
page 33
10.6 Making the Gas Connection
1. Connect the gas supply to the G
1
/
2
(
1
/
2
in BSPT Internal) gas tap. This is located on the lower right side of the boiler, access by hinging down the PCB
housing (see Fig. 32 ).
10.7 Fitting The Flue
Before fitting the flue, check the condensate drain integrity (see section 10.5 ).
IMPORTANT: The flue should always be installed with at least 1.5° fall from terminal to elbow, to allow condensate to run back to the boiler.
HORIZONTAL FLUE
1. The standard flue is suitable for lengths 270mm minimum to 800mm maximum (measured from the edge of the flue elbow outlet).
Rear Flue: maximum wall thickness - 630mm
Side Flue: maximum wall thickness - 565mm (left or right)
2. For rear exit - measure the wall thickness ( Fig. 26 ) and to this dimension add 181mm.
This dimension to be known as (X).
i.e. (X) = wall thi 181
3. Take the flue and mark off (X) from the terminal end as indicated in the diagram ( Fig. 27 ).
Check your dimensions.
The flue tubes are fixed together. Cut through both tubes whilst resting the flue on the semi-circular packing pieces. Deburr both tube ends.
4. For side exit - measure the distance from the edge of the wall plate to the inner face of the wall ( Fig. 26 ) and to this dimension add the wall thickness
+ 250mm.