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the AC equipment under the Falcon control. These settings are optional but if set correctly they can
significantly improve the Falcon zoning performance.
Fixed capacity AC systems especially require a minimum amount of air flow through them to run
effectively, without this minimum flow requirements being met the efficiency (and health) of the AC
system may suffer. The Falcon zone control system
must know when it’s safe to run
the heating or cooling
systems and when unsafe. The Falcon ideally also needs to know if there is too much demand for the
available capacity of the HVAC system.
For Example, a hypothetical building has 4 zones that requires heating.
Each zone is an identical size and each zone has identical demands. The
fixed capacity AC system controlling these 4 zones has too much capacity
to run just one zone alone, one zone alone calling heating will restrict air
flow through the AC system to much potentially causing damage to the ducts or to the AC system itself.
Two zones calling is ok, but not ideal. Any 3 zones calling is perfect however when all 4 zones are calling
the AC system heating at the same time the AC system st
ruggles and can’t meet
the total demand for
heating, so all 4 zones suffer.
The Falcon zone settings menu permits the installer to define the minimum and maximum capacity of the
AC system for heating and cooling and apply that to when zones can be heated (or cooled).
By using the Falcon zone control settings in the above example, the Falcon will not run heating if any one
zone calls; it will wait for more than 1 zone to call before staring the AC system in heating mode. When 2
zones call the Falcon will start the system in heating mode but can restrict fan speed to low (when AC
sys
tems with 3 fan speeds are used) or additionally open a “spill” or “relief” damper to move excess
capacity to a communal area thereby easing the load on the AC system. If any 3 zones call the Falcon will
close the “spill” or “relief” damper and permit high
er fan speeds to operate. If 4 zones are called, the
Falcon will intelligently select the 3 most important zones and use the AC system to heat those, when one
of those 3 reach temperature the Falcon will then heat the last zone. When only one zone remains needing
heating (hopefully not too much now) the Falcon will shut the AC system down to protect it.
In the real world not all zones are created equal and not all zones have an identical demand as shown in
the example to the right. In this case zone 4 if called alone is ok, as is zone 2, but zone 1 and 3 are both
too small to run alone or even together if both zones demand heating as their combined size is still below
the safe value to run the AC system in heating mode.
The Falcon overcomes these issues by using an easy to
understand “scoring”
system. The Falcon zone scoring system
is relative to the building and not based on a fixed score that is
directly proportional to M
3
of zone size.
Simply put - the bigger the zone in the building relative to all
the others zones in the building, the higher the “score” you
give that zone.
