Addison TRS Series - Grounding Requirements; Control System Wiring Specifications; Ductwork Installation Guidelines; Condensate Piping Requirements

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INSTALLATION (CONT’D)
Power wiring may enter the Rooftop Unit through the through the unit base and roof curbs on all models. Install conduit
connectors at the entrance locations. External connectors must be weatherproof.
Grounding
All units must be properly grounded. The ground lug is provided for this purpose. DO NOT use the ground lug for
connecting a neutral conductor. The unit must be electrically grounded in accordance with local codes, or in the absence
of local codes, with the NEC ANSI/NFPA 70 1981.
Once it is established that supply voltage is within the utilization range, check and calculate if an unbalanced condition
exists between phases. Calculate percent voltage unbalance as follows:
Contact power company if phase unbalance exceeds 2%.
Control System Wiring: For commercial equipment the following table lists the minimum size of 24 volt class 2 wire to be
used.
Note: Wiring - Consult the wiring diagram furnished with the unit. These units are custom designed for each application.
The unit wiring diagram is located inside the control panel of each unit.
Ductwork
Properly sized and installed ductwork is critical to reliable performance of the unit and system. The TRS Series is down
flow (vertical), horizontal supply and 100% outside air or horizontal supply and return duct connections with the use of a
tall horizontal duct curb. All duct connections with the use of a curb are to be field sized and cut. All ductwork must be
installed according to local codes, practices and requirements.
Industry manuals should be used as a guide to sizing and designing the duct system. Ducts passing through
unconditioned spaces must be well insulated with vapor barrier to prevent condensation.
Condensate Piping
A condensate trap must be provided by customer. Drainage of condensate directly onto the roof is acceptable if permitted
by local codes. It is recommended that a small drip pad of either stone, or tar, wood or metal be provided to prevent any
possible damage to the roof. If condensate is to be piped into the building drainage system, the drain line must penetrate
the roof external to the unit. Refer to local codes for additional requirements.