Duct System And Water Piping - York YBS006-070 Installation Manual

LX COMPACT SERIES INSTALLATION MANUAL
Duct System
An air outlet collar is provided on vertical top flow units and all
horizontal units to facilitate a duct connection. A flexible connector
is recommended for discharge and return air duct connections
on metal duct systems. Uninsulated duct should be insulated
with a minimum of 1-inch duct insulation. Application of the
unit to uninsulated ductwork in an unconditioned space is not
recommended as the unit's performance will be adversely affected.
If the unit is connected to existing ductwork, check the duct
system to ensure that it has the capacity to accommodate the air
required for the unit application. If the duct is too small, as in the
replacement of heating only systems, larger ductwork should be
installed. All existing ductwork should be checked for leaks and
repaired if necessary.
Water Piping
The proper water flow must be provided to each unit whenever the
unit operates. To assure proper flow, use pressure/temperature
ports to determine the flow rate. These ports should be located at
the supply and return water connections on the unit. The proper
flow rate cannot be accurately set without measuring the water
pressure drop through the refrigerant-to-water heat exchanger.
The duct system should be sized to handle the design airflow
quietly and efficiently. To maximize sound attenuation of the unit
blower, the supply and return plenums should include an internal
duct liner of fiberglass or constructed of ductboard for the first few
feet. On systems employing a sheet metal duct system, canvas
connectors should be used between the unit and the ductwork. If
air noise or excessive airflow is a problem, the blower speed can
be changed.
All source water connections on commercial units are fittings that
accept a male pipe thread (MPT). Insert the connectors by hand,
then tighten the fitting with a wrench to provide a leakproof joint.
When connecting to an open loop (groundwater) system, thread
any copper MPT fitting into the connector and tighten in the same
manner as described above.
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