Filters - Lennox MERIT Series Installation Instructions Manual

Horizontal Application
Unit Installed on Platform
Line contact is permissible
See the unit nameplate for
clearances.
GAS
ENTRY
SERVICE PLATFORM
Figure 13
CAUTION
If this unit is being installed in a space serviced by an
exhaust fan, power exhaust fan, or other device which
may create a negative pressure in the space, take care
when sizing the inlet air opening. The inlet air opening
must be sized to accommodate the maximum volume
of exhausted air as well as the maximum volume of
combustion air required for all gas appliances serviced
by this space.
WARNING
Improper installation of the furnace can result in
personal injury or death. Combustion and flue products
must never be allowed to enter the return air system or
the living space. Use screws and joint tape to seal the
return air system to the furnace. In platform installations
with bottom return air, the furnace should be sealed
airtight to the return air plenum. A door must never be
used as a portion of the return air duct system. The base
must provide a stable support and an airtight seal to the
furnace. Allow absolutely no sagging, cracks, gaps, etc.
The return and supply air duct systems must never be
connected to or from other heating devices such as a
fireplace or stove, etc. Fire, explosion, carbon monoxide
poisoning, personal injury and/or property damage could
result.
The blower access panel must be securely in place when
the blower and burners are operating. Gas fumes, which
could contain carbon monoxide, can be drawn into living
space resulting in personal injury or death.

Filters

This unit is not equipped with a filter or rack. A field-pro-
VENT
vided high-velocity filter is required for the unit to operate
PIPE
properly. Table 1 lists recommended filter sizes. A filter
must be in place any time the unit is operating.
Furnace Cabinet
Width
A - 14-1/2"
B - 17-1/2"
C - 21"
D - 24-1/2"
If a highefficiency filter is being installed as part of this
system to ensure better indoor air quality, the filter must
be properly sized. Highefficiency filters have a higher
static pressure drop than standardefficiency glass/foam
filters. If the pressure drop is too great, system capacity
and performance may be reduced. The pressure drop
may also cause the limit to trip more frequently during
the winter and the indoor coil to freeze in the summer,
resulting in an increase in the number of service calls.
Before using any filter with this system, check the
specifications provided by the filter manufacturer against
the data given in the appropriate Lennox Product
Specifications bulletin. Additional information is provided
in Service and Application Note ACC002 (August 2000).
Page 11
WARNING
TABLE 1
Filter Size
Side Return Bottom Return
16 X 25 X 1 (1) 14 X 25 X 1 (1)
16 X 25 X 1 (1) 16 X 25 X 1 (1)
16 X 25 X 1 (1) 20 x 25 x 1 (1)
16 X 25 X 1 (2) 24 x 25 x 1 (1)
IMPORTANT