CleaverBrooks ClearFire CFC-E - Page 47

CFC-E Installation Manual
Part No. 750-459 2-11
Use ‘wye’ connections (not ‘tees’) to connect each boiler to the common breeching (see Examples 1
and 2 below).
Breeching should be sized upward when necessary to accommodate additional boilers (see Example
3). As a rule of thumb, the cross-sectional area of any ductwork downstream of a wye connection should
be equal to or greater than the combined area of the incoming vent sections.
When multiple boilers are connected in a CB Falcon-controlled lead/lag network, a ‘Fan rate during off
cycle’ feature is available. When a boiler goes off line and completes a post purge, the fan will continue
to run at a user-selectable rate. This feature provides a further measure to prevent flue gas from flowing
back into the boiler.
EXAMPLE 1
;
45
o
6”
10”
14”
6” 6”
6”
3
GOOD
BAD