Sterling QVSD - Manual (Page 7)

7
If uniform air distribution is not obtained, install additional
baffl es and/or turning vanes in the ductwork.
Access panels large enough to observe smoke and
refl ected light, and to detect the presence of leaks in the
heating equipment, are required both upstream and
downstream from the gas duct furnace. These panels
must be sealed to prevent air leaks. If allowed by local
regulations, install canvas connectors between the
ductwork and fan discharge opening to eliminate the
transmission of sound.
Figures 2 & 3 illustrate recommended ductwork designs
for both the straight-through and elbowed air inlet
arrangements.
AIR FLOW: The installation is to be adjusted to obtain an
air throughput within the range specifi ed on the appliance
rating plate.
Figure 2 - Recommended Design for Field
Installation of Ductwork for
Straight-through Arrangement
Figure 3 - Recommended Ductwork Design
for Elbowed Arrangement
INSTALLATION (Continued)
BYPASS: When a gas duct furnace is installed to operate
in conjunction with a summer air conditioning system, the
cfm air delivery of the system blower should be adjusted
to meet the design air volume requirements for cooling.
If this cfm delivery is greater than that required for heating,
resulting in a low air temperature rise, install a damper
bypass around the gas duct furnace to bypass a portion
of the air.
SUSPENSION: Refer to Figure 4 for typical suspension
arrangements.
The Separated Combustion Duct
Furnace must be hung level from side to side, and
from front to back, from four suspension points
provided at the top of the unit. Failure to do so will
result in poor performance and or premature failure
of the unit. Refer to Figure 4 for typical suspension
arrangements. DO NOT mount duct furnaces in series
(one in front of another).
NOTICE: When mounting duct furnaces side by side,
units must have opposite side gas connections
(determined by Digit #6 - Furnace Type in the unit
number). Minimum safety clearances must also be
maintained; see Table 3. When service/accessibility
clearances are greater than minimum safety
clearances, service/accessibility clearances take
precedence. See “Accessibility” section under
“Installation”.
Ensure that all hardware used in
the suspension or for duct furnace is more than
adequate for the job. Failure to do so may result
in extensive property damage, severe personal
injury or death!