A.O. Smith BFC-28 - Page 34

Installation
32 Instruction manual BFC
3
is
Concentric roof flue terminal specifications C33
3.9.4 Parallel connections
The table states the maximum pipe lengths for parallel systems. The maximum
pipe length depends on the chosen diameter.
Warning
Install flue gas discharge pipe runs with a run-off of 5 mm per metre towards
the water heater.
Chimney flue requirements for parallel systems
You must use the longest pipe when calculating the pipe length. For example, if
the chimney pipe is 10 metres and the air supply pipe is 8 metres, use 10 metres
as the length for the calculation. Next, add the L
equivalent
for every 90° and 45°
bend to this 10 metres, in both the air supply and flue gas outlet. The following
practical example illustrates how to use the table.
Subject Description
Roof conduit set:
• 1x roof conduit
(incl. clamping ring)
• 1x pipe 1000 mm
• 1x adhesive sheet
Art. No. BFC 28, 30, 50, 60 0304 423
1
BFC 80, 100, 120 0306 855
1
Manufacturer Muelink & Grol
Type M2000 DDV HR-C
Pipe material Construction Concentric
Flue gas discharge Thick-walled aluminium with lipped sealing ring.
Air supply Thin-walled galvanised sheet steel.
Pipe diameters Flue gas discharge BFC 28, 30, 50, 60 Ø 100 mm
BFC 80, 100, 120 Ø 130mm
Air supply BFC 28, 30, 50, 60 Ø 150 mm
BFC 80, 100, 120 Ø 200 mm
(1) No other roof flue terminal may be used. Use this item number to order the roof flue terminal set from the
supplier, manufacturer or wholesalor.
Appliance Diameter
1
Maximum
total
length
L
equivalent
90
o
bend
L
equivalent
45
o
bend
BFC 28, 30, 50, 60 100 mm 55 m 4.6 m 1.2 m
BFC 80, 100, 120 130 mm 65 m 2.4 m 1.4 m
BFC 28, 30, 50, 60 130 mm 100 m 2.4 m 1.4 m
BFC 80, 100, 120 150 mm 100 m 2.6 m 1.6 m
1) Parallel systems with diameter of 100 mm or 130 mm. If the maximum total
length when using diameter 100 mm is insufficient, diameter 130 mm should
be used. If the maximum total length when using diameter 130 mm is
insufficient, diameter 150 mm should be used. Any diameter enlargement
must be carried out on both air supply and flue gas outlet.