Vertical
Flues
(ii)
(i)
IMPORTANT: All flue systems must be securely supported at least once every metre. Suitable pipe supports are available as accessories.
1m Min to
15m Max
| 8.0 | Flue Options |
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| 8.2 | Twin & Vertical Flue Systems | ||
| 1. Maximum permissible equivalent flue lengths are:- | |||
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| (60/100) | (80/125) |
| Vertical Concentric | 10 metres | 20 metres | |
| Vertical Twin Pipe | 15 metres |
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| 2. Any additional “in line” bends in the flue system must be | |||
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| Their equivalent lengths are:- |
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| Concentric Pipes: |
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| 135° bend |
| 0.5 metres |
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| 93° bend |
| 1.0 metres |
| Twin Flue Pipe |
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120mm Min |
| 135° bend |
| 0.25 metres |
| 91.5° bend |
| 0.50 metres | |
apart |
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| The elbow supplied with the standard horizontal telescopic | |||
| flue kit is not included in any equivalent length calculations | |||
Y | NOTE: Flue length is measured from point (i) to (ii) as | |||
shown. |
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(ii)
(i) | T |
Vertical Flues
(Twin Pipe)
Total Equivalent Length = |
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A+B+C+1x90°Bend |
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| Roof |
All vertical and angled runs must be included, |
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| Terminal |
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measured from the boiler adaptor (point X) to the |
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joint with the flue terminal (point Y). One 91.5° |
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bend or two 135° bends can be included without |
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reduction of the flue length. |
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If further elbows are required the flue length must |
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be reduced by the following amounts:- |
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1 metre for each 91.5° bend | (ii) |
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0.5 metre for each 135° bend |
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B
This bend is equivalent to 1 metre
A
(i)
22© Baxi Heating UK Ltd 2012
600mm Min |
| Mini Terminal | |
apart |
| on Air Duct | |
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| (sited in loft) |
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1m Min
to
15m Max
Q
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| length for this example | ||||
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| AIR DUCT |
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| Equivalent | No of | Sub total | ||
| Length Value |
| fittings/pipes |
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1m extension | 1m |
| 5 |
| 5.0m |
135°bend | 0.25m |
| 2 |
| 0.5m |
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91.5°bend | 0.5m |
| 2 |
| 1.0m |
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| Equivalent Length Air Duct = 6.5m | ||||
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| FLUE DUCT |
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| Equivalent | No of | Sub total | ||
| Length Value |
| fittings/pipes |
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1m extension | 1m |
| 5 |
| 5.0m |
135°bend | 0.25m |
| 2 |
| 0.5m |
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91.5°bend | 0.5m |
| 2 |
| 1.0m |
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| Equivalent Length Flue Duct = 6.5m | ||||
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