Instruction Manual

AIR DISTRIBUTION DUCTS
MB, MB-HW: Installation, Operation, and Maintenance Instructions
5
AIR DISTRIBUTION DUCTS
All duct work must be installed in accordance with National Fire Protection
Association Codes 90A and 90B. Supply and return duct system must be
adequately sized to meet the system’s air requirements and static pressure
capabilities. Ducts should be adequately insulated to prevent condensation
during the cooling cycle and to minimize heat loss during the heating cycle.
The ducts should be insulated with a minimum of 1-inch insulation with a vapor
barrier in conditioned areas or 2-inches minimum in unconditioned areas. All
return air must be filtered to prevent dirt buildup on the coil surface. If there is
no ducted return, applicable installation codes may limit the unit to installation
only in a single story residence. In many cases it is acceptable to use ducting of
the same size as the fan coil connections. However, unique arrangements or
long duct runs must be confirmed by a local professional. The manufacturer
will not be responsible for misapplied equipment.
ELECTRICAL
WARNINGS:
Electric Shock Hazard
•
Disconnect all power supplies before servicing; lock out/tag out to
prevent accidental electrical shock. Note: there may be multiple power
sources.
•
Use copper conductors only.
•
Install all parts and panels before operating.
•
Failure to follow these warnings can result in injury or death.
All wiring must comply with local and national code requirements. Units are
provided with wiring diagrams and nameplate data to provide information
required for necessary field wiring.
These units are provided with a Class 2 transformer for 24-volt control circuits.
Should any add-on equipment also have a Class 2 transformer furnished, care
must be taken to prevent interconnecting outputs of the two transformers by
using a thermostat with isolating contacts.
WARNING: Units with ECM motors have line voltage power applied at all times. Make
sure power is disconnected before servicing.