Whilst it is always our intention to fully assist, it is essential to recognise that all information given by the company in response to an enquiry of any nature is provided in good faith and based
upon the information provided with the enquiry. We recommend that advice should always be checked with your installer or contract partner. Consequently, the company cannot be held
responsible for any liability relating to the use or repetition of such information or part thereof. In addition, whilst making every reasonable effort to monitor the performance and quality of
our supply, installation and service network, we do not accept responsibility for the workmanship or operation of any third party company that the company may have promoted either in
conversation, e-mail, or other communication. Similarly, the views and opinions expressed in communication with individuals within the company may not reflect that of the business as a whole.
You can find this, and all issued technical bulletins on the Worcester website at:
13
Worcester, Bosch Group, Cotswold Way, Warndon, Worcester WR4 9SW Technical Services: 0330 123 3366 | [email protected]
Bosch Flue and Ventilation Quick Reference Guide 2022
Open flue terminations
5U (uncorrected chimney height) calculations for assessing flue height and aggregated groups of flue terminals
•
Where a group of individual flues terminate close to each other and within 5U they must be aggregated, and the
value used for the flue height calculation.
Flue termination height above structures (distance X) for appliances up to 333 kW
(Refer to Figure 15)
•
For terminals fitted to a pitched roof the end-piece termination (as shown in
Figure 15
) should be at least 1.5m from the roof
surface when measured horizontally and at least distance ‘
X
’ above the roof line (See table above for correct ‘
X
’ value
calculations).
•
For terminals fitted to a flat roof (where there is no general access) the end-piece termination (Base of the grill or terminal
position) should be located at least distance ‘
X
’ (See table above) above the roof line at the point where it exits the roof (See
Figure 14
).
•
Where the terminal is located within 2.5m of an adjacent structure the terminal should be at least distance ‘
X
’ above the structure
(See table above for distance ‘
X
’ and reference
Figure 15
).
Terminations for Ridged and flat roof configurations
Please note:
Flue diameters specified 170mm or less require a terminal that is designed to minimize the ingress of rain or birds.
Reference
Description
Unit
50
kW
65
kW
85
kW
100
kW
125
kW
145
kW
5U (5 x Uncorrected chimney
height)
For determining if low level flue terminations
must be treated as a group
mm
1221
1465
1695
1869
2110
2337
IGEM Calculation used
Description
Unit
50
kW
65
kW
85
kW
100
kW
125
kW
145
kW
Distance X – (
IGEM-UP-10, Fig. 8)
(Distance X = 1.5225 x (net heat input kW) + 493.43)
Distance for Flue
terminals located on a
roof.
mm
566
592
619
641
674
707
Figure 15
