Technical data

14
Alpha 240XP and 240XE - Installation
4.7 FIT A FLUE EXTENSION - Figs. 12, 13
Note: 1. The maximum flue assembly length must not exceed a length of 4 metres.
2. If the flue is more than 1 m, the restrictor must be removed from the flue adaptor (see Fig. 13), by removing the screw
and lifting out the restrictor.
1. Withdraw the inner flue duct from the outer air duct supplied with the boiler.
2. Withdraw the inner flue duct from the extension. Secure the two ducts together using the clamp supplied with the
extension, ensure that the ducts are butted together and the clamp is central over the joint.
3. Secure the outer ducts together using the silicone seal and clamp supplied with the extension. Lubricating the silicone
seal with a soap solution will aid assembly.
4. With all the ducts assembled together, cut to the following lengths:-
Rear flue Outer air duct length = finished wall thickness + 110 mm.
Inner flue duct length = finished wall thickness + 147 mm.
Side flue Outer air duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 145 mm.
Inner flue duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + 182 mm.
5. When measuring the outer duct, measure from the end of the tube as shown in Figs. 12 and 13.
6. Cut both the inner and outer ducts to length.
Note: Do not cut the outer duct end with the two holes, these are for securing the terminal.
Ensure that all cuts are square and burr free.
Fig. 13 - Side flue
Fig. 12 - Rear flue
Outer air duct length
Inner flue duct length
Outer duct clamp and seal
90° bend
Boiler
Terminal
Flue sealing collar
20
20
77
90
190
20
20
36
125
225
225
20
77
120
Outer duct clamp
and seal
Inner duct clamp
Seal
Boiler
Outer air duct length
Inner flue duct length
Bend clamp
and seal
Screw
Note: For horizontal flue ensure there
is a slight downward slope
towards terminal.
120
Ensure joint of inner
clamp is at bottom
Inner duct clamp
Restrictor