Multiple Outdoor Units; Torque Requirements For Caps And Fasteners; Indoor Unit Installation; Unit Placement Considerations - Lennox MHB Series Installation, Instruction And Service Manual

Multiple Outdoor Units

CLEARANCE NOTES FOR MULTIPLE UNITS:
If the height of the wall (C) is less than or equal to the height of the smallest unit (A), the distance from the unit to the wall (B) must be a minimum of 10 inches (254 mm).
If 1/2 the height of the unit (A) is less than the height of the wall (C), the distance from the unit to the wall (B) must be a minimum of 12 inches (305 mm).
If the height of the wall (C) is greater than the height of the unit (A), the distance from the unit to the wall (B) must be a minimum of 20 inches (508 mm).
Torque Requirements for Caps and
Fasteners
When servicing or repairing HVAC components, ensure
the fasteners are appropriately tightened. "Table 2. Torque
Requirements" on page 6 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 factory­torqued from 9 ft.­lbs.
(12 N*m) 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 C­08­1
for further details and information.
Table 2. Torque Requirements
Parts
Service valve cap
Sheet metal screws
Unit
Height (A)
Figure 10. Multiple Outdoor Unit Clearances - Inches (mm)
Recommended Torque
U.S. Newton-Meter- N
8 ft.­lb. 11
16 in.-lb. 2
Table 2. Torque Requirements
Parts
Machine screws #10
Compressor bolts
Gauge port seal cap

Indoor Unit Installation

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.
6
Recommended Torque
U.S. Newton-Meter- N
27 in.-lb.
7 ft.-lb.
8 ft.­lb.
CAUTION
Height of
Wall (C)
3
10
11