7
Torque Requirements for Caps and Fasteners
When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. “Table 1. Torque
Requirements” provides torque values for fasteners.
IMPORTANT
Only use Allen wrenches of sufficient hardness (50Rc -
Rockwell scale minimum). Fully insert the wrench into
the valve stem recess.
Service valve stems are factory-torqued from 9 ft.-lbs.
(12 N) for small valves, to 25 ft.-lbs. (34 N) for large
valves) to prevent refrigerant loss during shipping and
handling. Using an Allen wrench rated at less than 50Rc
risks rounding or breaking off the wrench, or stripping
the valve stem recess.
See the Lennox Service and Application Notes C-08-1
for further details and information.
Table 1. Torque Requirements
Parts
Recommended Torque
U.S.
Newton-Meter- N
Service valve cap
8 ft.-lb.
11
Sheet metal screws
16 in.-lb.
2
Machine screws #10
27 in.-lb.
3
Compressor bolts
7 ft.-lb.
10
Gauge port seal cap
8 ft.-lb.
11
Indoor Unit Installation
CAUTION
In order to avoid injury, take proper precaution when
lifting heavy objects.
Unit Placement Considerations
AVOID
Do not install the unit in the following locations:
• Areas exposed to petrochemicals or petrochemical
products.
• Areas exposed to salt or other corrosive materials or
caustic gases.
• Areas exposed to extreme voltage variations (such as
factories.
• Tightly enclosed areas that may impede service of the
unit.
• Areas exposed to fossil fuels (such as oil or gas in
kitchens).
• Areas exposed to strong electromagnetic forces.
• Areas exposed to acids or alkaline detergents.
DO
• Place the unit so that it is not exposed to direct sun-
light.
•
Ensure the structural ceiling can support the weight of
the unit.
• Select a location where condensate line will have the
shortest run to a suitable drain per local codes.
•
Allow sufficient space around unit for proper operation
and maintenance.
• Install unit a minimum of 3 feet (1m) away from any
antenna, power cord (line) radio, telephone, security
system, or intercom. Electrical interference and radio
frequencies from any of these sources may affect op-
eration.
Be sure to instruct customers how to properly operate
the unit (especially maintenance of air filter, and
operation procedure) by having them carry out operations
themselves while looking at the manual provided with the
controller
Floor Installation
• Locate a suitable position within the space where
maintenance access and supply air will not be restrict-
ed or affected by obstacles. See “Figure 4. Indoor Unit
Clearances - Inches (mm)” on page 6 for minimum
clearances.
• Place the MFMA on a wall which is both capable of
supporting the unit’s weight and which is constructed
to enable the unit to fit flush on the wall. An uneven
wall may lead to vibration and subsequent unit dam-
age.
Units are wall mounted using two
factory-provided
hanging brackets.
Affix the wall mounts with a field-provide tapping screws (6) onto the
wall.
Hook
Tapping
screw
Washer
˘
6mm
7-11/16”
(195mm)
Hanging
Brackets
Mount the unit onto the two hanging brackets
The bottom of unit can touch the floor or remain suspended, but the unit must be installed
vertically.
Figure 5. Mounting Unit to Wall
