Space-Ray ADU25 Installation And Operation Instruction Manual page 49

Fig. 34
16.1 Type A :
2
Outside (ducted) combustion air supply. When installed in a dusty or polluted atmosphere, the heater
should be fitted with a ducted supply of clean fresh air. A length of 100mm flexible ducting should be
installed between the Control Box Air Inlet and any rigid ducting and be secured to the Air Inlet with hose
clips.
Where outside combustion air is ducted directly to the burner(s) the low level natural ventilation openings
shall be not less than 50 of the areas given in 6.4.2.1 above.
16.2 Type B :
22
When installing external flue single duct systems with ducted combustion air supply the distance between
the flue terminal and fresh air intake shall be no less than 1 m for both vertical and horizontal systems
16.3 TypeC :
12
The following figure shows the typical arrangements for concentric sidewall flues, see Table 18 for 90°
bend equivalent lengths. The bends shown in the illustrations connecting the combustion air intake to the
concentric ducts is calculated into the overall length. For example a system with one additional
150/100mm Ø concentric 90° bend can be installed with 1m 100mm flue single pipe and the
combustion air single pipe as shown with 5.5m of 150/100mm Ø straight concentric flue. (8m – 2.5m
from Table 18)
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Form #44201100
Oct 2019