Multi F Engineering Manual

Rooftop Installations
If the outdoor unit is installed on a roof structure, be sure to level the unit. Ensure the roof structure and anchoring method are adequate for 
the unit location. Consult local codes regarding rooftop mounting. 
PLACEMENT CONSIDERATIONS
Selecting the Best Location for the Outdoor Unit, continued.
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heat or steam like discharge from boiler stacks, chimneys, steam relief ports, other air conditioning units, kitchen vents, plumbing vents, 
and other sources of extreme temperatures.
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Ocean winds
Ocean winds
Ocean winds
Windbreaker
Planning for Snow and Ice
In climates that experience snow buildup, place the unit on a raised platform to ensure proper condenser airflow. The raised support platform 
must be high enough to allow the unit to remain above possible snow drifts. Mount the unit on a field-provided stand that is higher than the 
maximum anticipated snowfall for the location. Design the mounting base to prevent snow accumulation on the platform in front or back of 
the unit case. If necessary, provide a field fabricated hood to keep snow and ice and/or drifting snow from accumulating on the coil surfaces. 
Use inlet and discharge duct or hoods to prevent snow or rain from accumulating on the fan inlet and outlet guards. Best practice prevents 
snow from accumulating on top of the unit. Consider tie-down requirements in case of high winds or where required by local codes. 
Oceanside Installation Precautions
• Install the outdoor unit on the side of the 
building opposite from direct ocean winds.
• Select a location with good drainage.
• Periodically clean dust or salt particles off of 
the heat exchanger with water.
• 
 Avoid installing the outdoor unit where it 
would be directly exposed to ocean winds.
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to be applied to the outdoor unit at oceanside 
locations.
If the outdoor unit must be placed in a 
location where it would be subjected to 
direct ocean winds, install a concrete 
windbreaker strong enough to block any 
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must be more than 150% of the outdoor 
unit, and be installed at least 27-1/2 
inches away from the outdoor unit to 
allow for airflow.
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• Include space for drainage to ensure condensate flows properly out of the unit when it is in heating mode. 
 Avoid placing the outdoor unit 
in a low-lying area where water could accumulate. 
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APPLICATION GUIDELINES | 193
Application Guidelines
MULTI 
F
MAX
MULTI 
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