Napoleon 9600E E-STAR Series, Installation And Operating Instructions Manual

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W415-2159 / D / 11.24.17
8
IOM IOM
3.0 FURNACE SIZING
The maximum hourly heat loss for each heated space shall be calculated in accordance with the procedures
described in the manuals of the
Heating, Refrigeration and Air Conditioning Institute of Canada (HRAI)
, or
by any other method which is suitable for local conditions, provided the results obtained are in substantial
agreement with, and not less than those obtained using the procedure described in their manuals.
In the United States,
“Manual J - Load Calculation,”
published by the Air Conditioning Contractors of America,
describes a suitable procedure for calculating the maximum hourly heat loss.
If the installation is a retro fi t application, do not rely on the capacity of the existing heating equipment as a
method to size the new furnace. Many of the heat transfer multiples listed in earlier versions of load calculation
manuals were much higher than those listed in more recent editions. It is possible that energy saving
measures have been completed since the installation of the existing furnace. This might include additional
insulation in the attic or walls, the application of sprayed foam insulation, the addition of storm windows and
doors, weather-stripping, caulking, etc.
Many of the older furnaces were equipped with large belt drive blower systems, operating at low RPM’s. If
replacing an existing furnace, be sure that the existing ductwork can handle the amount of air
fl ow necessary
for a reasonable temperature rise. Most older gas furnaces operated with a system temperature rise of 70 -
100°F (39 - 56°C). These furnaces are designed to operated with a system temperature rise (
∆ T) of 35 - 70°F
(20 - 38.9°C), refer to Table 1 for speci fi c models.. If the
furnace selected has an identical output capacity as the
original furnace, a substantial increase in system air
fl ow will
be necessary.
Existing ductwork should be assessed for its air handling
capabilities.
The
“Equal Friction Chart,”
as published by ASHRAE
and HRAI, is the basis for the various air duct calculators
available through heating supply companies. Following the air
velocity guide lines, according to the
“Equal Friction Chart,”
or a slide rule air duct calculator, a typical 6" (152mm) round
duct has a capacity of approximately 100 cfm.
H7.0.5 H7 0 5
NOTE:
The return air system is equally as important as the supply air system. An under-sized return air system
will prevent suf
fi cient quantities of air from reaching the supply air system and will consequently reduce
the service life of the furnace and its components.
Model Delta T
NEV040T2A 35-65°F (20-36°C)
NEV060T3A
40-70°F (22.2-38.9°C)
NEV080T3A
NEV080T4A
NEV100T5A
NEV120T5A
H12.15.6A
TABLE 1 - RANGE OF TEMPERTURE RISE