WarmFlow WS18, Руководство пользователя

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3.6.3 Extended Flue Assembly
The flue supplied with the appliance (shown in Figure 66) can be extended if necessary to
ensure the flue outlet position complies with the requirements set out in Figure 67.
IMPORTANT – Extending the supplied flue will increase resistance and demand on the exhaust
fan of the appliance. As a result, it will be necessary to service the appliance and clean the flue
more frequently if the flue is extended (Refer to Sections 4.2 and 4.3). Extended flues are also
more difficult and time consuming to clean correctly. The level of difficulty and time involved
increases as the flue length and number of bends in the extended flue increases. More frequent
and time consuming servicing and cleaning activities associated with extended flues results in
higher operating costs for the appliance when compared to an installation where the standard
short flue is installed. (Refer to Figure 67).
Extending the flue should be avoided where possible, however flue outlet position and
compliance with the combustion appliance and fuel storage systems directive of current local
building regulations is of primary importance. Flue extensions can be avoided by careful
consideration of where the appliance is sited in relation to nearby buildings prior to installation.
If a flue extension is unavoidable, every effort should be made to keep the complete flue
construction as short as possible and as straight as possible i.e. without bends to reduce
resistance through the flue system and with due consideration given to access for cleaning.
The following rules MUST be observed when installing an extended flue:
•
The flue installation must be completed by a Warmflow engineer or qualified biomass
engineer
•
The flue installation must comply with the requirements set out in Figure 67.
•
Keep the extended flue as short as possible
•
Keep the extended flue as straight and vertical as possible i.e. avoid using bends and
long diagonal sections.
•
If the use of bends is unavoidable, always use them in pairs so that the inlet to the
lowermost bend is vertical and the outlet from the uppermost bend is vertical.
•
Never use more than four 45 ⁰ bends in a complete extended flue system.
•
Ensure the extended flue does not exceed the maximum allowable equivalent length of
6.0 metres. NOTE – 1 x 45
⁰
bend has an equivalent length of 0.5m.
Example Calculations:
Example 1: No bends fitted Example 2: 2 x 45 ⁰ bends fitted
Length of straight flue 6.0m Length of straight flue 6.0m
No bends 0.0m 2 x 45
⁰
Bends 1.0m
Equivalent length 6.0m Equivalent length 7.0m
Equivalent length within the max. allowable Equivalent length over max. allowable
INSTALLATION ACCEPTABLE. INSTALLATION NOT ACCEPTABLE.