Technical data
15
Alpha 500E - Installation
Fig. 14 - Rear flue
Fig. 15 - Side flue
4.8 FIT A FLUE EXTENSION - Figs. 14, 15
Note: The maximum flue assembly length must not exceed a length of 4 metres.
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 + 35 mm.
Inner flue duct length = finished wall thickness + 112 mm.
Side flue Outer air duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + a mm.
Inner flue duct length = finished wall thickness + the distance from the inside wall to the side of the boiler + b mm.
Note: L/H side a = 300, b = 377. R/H side a = 50, b = 127.
5. When measuring the outer duct, measure from the end of the tube as shown in Figs. 14 and 15.
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.
7. Fit the flue terminal to the outer duct by inserting it into the end with two holes. Align the holes and secure with the two
screws provided.
Outer air duct length
Inner flue duct length
Outer duct clamp and seal
90° bend
BOILER SIDE
Terminal
Sealing plate
(optional)
20
15
72
60
160
20
20
20
325
175
(RHS)
425
(LHS)
15
72
115
Outer duct clamp
and seal
Inner duct clamp
Seal
BOILER
FRONT
Outer air duct length
Inner flue duct length
Bend clamp
and seal
Note: For horizontal flue ensure there
is a slight downward slope
towards terminal.
115
Inner duct clamp
120
40
Note: 40 mm gap between
boiler 90° bend and
outer air duct
20
40