Unit Support; Duct Connection - Lennox LCH036 Installation Instructions Manual

WARNING
Electric shock hazard and danger of
explosion. Can cause injury, death or
product or property damage. Turn off
gas and electrical power to unit before
performing
servicing operations on the unit. Follow
lighting instructions attached to unit
when putting unit back into operation
and after service or maintenance.
IMPORTANT
The Clean Air Act of 1990 bans the intentional vent­
ing of refrigerant (CFC's and HCFC's) as of July 1,
1992. Approved methods of recovery, recycling or
reclaiming must be followed. Fines and/or incar­
ceration may be levied for non-compliance.
CAUTION
Danger of sharp metallic edges. Can cause injury.
Take care when servicing unit to avoid accidental
contact with sharp edges.
NOTICE
Roof Damage!
This system contains both refrigerant and oil.
Some rubber roofing material may absorb oil,
causing the rubber to swell. Bubbles in the rubber
roofing material can cause leaks. Protect the roof
surface to avoid exposure to refrigerant and oil
during service and installation. Failure to follow
this notice could result in damage to roof surface.

Unit Support

In downflow discharge installations, install the unit on a
non-combustible surface only. Unit may be installed on
combustible surfaces when used in horizontal discharge
applications or in downflow discharge applications when
installed on an S6CURB roof mounting frame.
NOTE - Securely fasten roof frame to roof per local codes.
A-Downflow Discharge Application
Roof Mounting with S6CURB
1- The roof mounting frame must be installed, flashed
and sealed in accordance with the instructions
provided with the frame.
2- The roof mounting frame should be square and level
to 1/16" per linear foot (5mm per linear meter) in any
direction.
any maintenance
3- Duct must be attached to the roof mounting frame
and not to the unit; supply and return plenums must
be installed before setting the unit.
Installer's Roof Mounting Frame
Many types of roof frames can be used to install the unit
depending upon different roof structures. Items to keep
or
in mind when using the building frame or supports are:
1- The base is fully enclosed and insulated, so an
enclosed frame is not required.
2- The frames or supports must be constructed with
non-combustible materials and should be square and
level to 1/16" per linear foot (5mm per linear meter)
in any direction.
3- Frame or supports must be high enough to prevent any
form of moisture from entering unit. Recommended
minimum frame height is 14" (356mm).
4- Duct must be attached to the roof mounting frame
and not to the unit. Supply and return plenums must
be installed before setting the unit.
5- Units require support along all four sides of unit base.
Supports must be constructed of steel or suitably
treated wood materials.
NOTE-When installing a unit on a combustible surface for
downflow discharge applications, an S6CURB roof
mounting frame is required.
B-Horizontal Discharge Applications
1- Units installed in horizontal airflow applications must
use an LARMFH30/36 horizontal roof mounting
frame. The supply air duct connects to the horizontal
supply air opening on the LARMFH30/36. The return
air duct connects to the unit horizontal return air
opening. Refer to unit dimensions.
2- Specified installation clearances must be maintained
when installing units. Refer to figure 1.
3- Top of support slab should be approximately 4"
(102mm) above the finished grade and located so no
run-off water from higher ground can collect around
the unit.
4- Units require support along all four sides of unit base.
Supports must be constructed of steel or suitably
treated wood materials.

Duct Connection

All exterior ducts, joints and openings in roof or building
walls must be insulated and weather-proofed with
flashing and sealing compounds in accordance with
applicable codes. Any duct passing through an
unconditioned space must be insulated.
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