Drolet DF02003, Installation And Operating Instructions Manual

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Heat Commander Furnace Installation and Operation Manual
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Example of surface calculation according to the number
of outlets used in the plenum:
Diameter of plenum
outlet (in)
Surface of plenum
outlet (in 2 )
Number of outlets
on the plenum
Total surface of
plenum outlets used
(in
2
)
6 28 6 170
The acceptable total area of secondary outlets would therefore be:
Diameter of
secondary outlet (in)
Surface of
secondary outlet
(in 2 )
Number of
secondary outlets
Total surface of
secondary outlets
used (in 2 )
4 12.5 9 112.5
5 19.5 1 19.5
6 28 1 28
The total area of the secondary outlets of this system would be
acceptable because it is equal to or slightly less than the total area
of the plenum outlets.
160
ACORDING TO THE NATIONAL BUILDING CODE, THE BTU/H PROVIDED BY AT
REGISTER MUST NOT EXCEED 10,250 BTU/H (3kW) AND THE HOT AIR
TEMPERATURE AT THE OUTLET OF A SECONDARY DUCT SHOULD NOT EXCEED
158 °F (70 °C).
Once your hot air distribution system is installed, make sure to measure the static pressure
in the start-off plenum. Adjust the opening at the end of each of distribution duct with a
shutter until you get a minimum static pressure 0.2” W.C. (50 Pa) at the plenum. The
recommended air velocity exiting the register should be between 500 and 750 feet per
minute.
5.5 Air return system and filter
The installation of an optional air return system connected to the blower housing will improve
the air circulation throughout the house (see
Appendix 3: Optional Fresh air return
adapter (AC01392) ). The use of the air filter option is recommended. The filter option will
significantly reduce dust circulation within the hot air duct and will prevent obstruction of the
blower (see
Appendix 2: Optional air filters (AC01390, AC01391) ).
NOTE: TO ENSURE ADEQUATE STATIC PRESSURE, THE SYSTEM SHOULD BE
BUILT IN A WAY THAT THE VOLUME OF COLD AIR RETURN IS AT LEAST EQUAL OR
SLIGHTLY HIGHER THAN THE VOLUME OF THE HOT AIR DISTRIBUTION.