Orion System Zoning - Manual (Page 11)

Orion Systems 11
Zoning Design Guide
This is a summary of the key items you need to con-
sider for the design and layout of a successful zoning
system.
It is important that you study the design guide for a
more in depth understanding of proper system design.
By following the design guide and these tips you can
eliminate many unnecessary headaches that occur when
the basic rules of zoning are not followed. Always con-
tact WattMaster Controls if you have any questions.
• Always group zones with similar load
profiles on the same HVAC unit.
• Never mix perimeter zones with interior
zones on the same HVAC unit.
• Each zoned HVAC unit should have a
minimum of 3 to 4 zones. Any less and you
should consult the factory.
• Each zoned HVAC unit can support a
maximum of 16 voting zones. Any more
zones and you should contact the factory.
• When using auxiliary heat for individual
zones, perimeter heat such as baseboard is
always preferred and more economical to
operate than a fan terminal unit with reheat
• If you have electric reheat coils mounted on
terminal units, it is recommended these be
fan powered terminals. Consult the factory
for further details concerning this application.
• If there is an economizer on the HVAC unit,
it is highly recommended, though not
required, that the Orion HVAC unit controller
controls the economizer.
• Pressure Independent Zones must always use
round dampers or VAV boxes, never
rectangular - no exceptions!
• Never attempt to use a zone control system
on a true VAV application. See “ Zoning
Systems Versus True VAV Systems” on page
5 of this guide for detailed information.
• Bypass dampers should always be sized for
60%-70% of the HVAC units rated CFM
• Even though the Orion system has
certain features to help protect your
equipment, never override or disconnect any
safety devices associated with the HVAC
unit
• To prevent low load cycling of the
equipment, a hot gas bypass system on the
first stage of cooling is highly recommended
Basics of Designing A Zoning System