RSF Woodburning Fireplaces ONYX AP Owner's Manual page 23

space and minimize cost. Maximum duct length should not exceed 50 feet from the fireplace to the furthest outlet.
There is a loss of about 15% performance at 50 feet. Also:
temperature reaches 180° F inside the ducting.
5. Locate the blower in a convenient location. The blower may be installed vertically or horizontally. The horizon-
tal installation can utilize either the supplied mounting bracket or, if you want to install the blower farther away
from the ceiling, you can use plumber's strapping. A vertical installation must include the mounting bracket.
Note: If you have an existing hot air system, you may safely 'tie in' to this hot air system. However, no hot air duct
is to be connected to the return air of another central heating system.
6. Connect the INLET of the blower to the ducting coming from the fireplace, using 8" diameter metal ducting (rigid
or flex). Any other size will not work properly. Use only metal ducting between the fireplace and the blower. You
may use plastic ducting after the blower, provided the temperature rating of the ducting is at least 250° F. Do
not use plastic ducting in a chase.
NOTE: The central heat ducting may be run at a 0" clearance to combustibles.
7. Attach the noise reduction collars to the blower using self-tapping screws.
8. Ductwork can then be run to the desired rooms. Up to six 5" or five 6" diameter runs can be installed from this
system.
NOTE: Runs must be balanced as air travels along the path of least resistance. Balance the airflow by diameter
and length of runs. Longer runs should have larger diameters. Houses vary in size and layout, so duct systems
must be specifically designed for each home. The diagrams on this sheet are examples only. The cross sectional
Example 1: tie-in to heat
plenum for circulation throughout all rooms
Figure 27: 2 examples of air circulation when tying-in to existing ductwork
ONYX AP Owner's Manual
Example 2: tie-in to
part of the duct system
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The blower automatically shuts off if the air
RSF Woodburning Fireplaces