Appendix A: VAV Zone Controller Points/Properties
Point Name/Description
Default/Range
Active Cooling Caller?
– VVT system only. Determines if the zone will be counted as a cool
caller for system cooling when the zone has a local demand for cooling.
D:
R:
Yes
No/Yes
Linkage Callers
– VVT system only. The minimum number of zones required to make the
air source go into heating or cooling mode. 1 is typical for systems with 8 zones or less.
For larger systems, increase the number by 1 for each 6 zones. For example, 3 linkage
callers for a 20 zone system.
D:
R:
1
1 to 32
System Mode Reselect Timer (minutes)
– Applies only to a VVT master. Defines how long
the system continues to operate in the current mode before it reassesses all zones while
the current demand is still active.
D:
R:
30
10 to 120
Linkage RH Type
– Determines if the VVT or VAV Master sends to the air source the
average or maximum values of all linked zone controllers that have a relative humidity
(RH) sensor.
D:
R:
Avg
Avg/Max
Linkage IAQ Type
– Determines if the Master controller sends to the air source the
average or maximum values of all linked zone controllers that have a CO
2
sensor for DCV
and IAQ control.
D:
R:
Max
Avg/Max
Air Source Mode
– If
Airside Linkage Status
is
Active
, this is the current mode of the
linked air source. If
Airside Linkage Status
is
Not Active
, this is the mode of the air source
as determined by the zone controller’s SAT sensor.
R:
OFF
WARMUP
HEAT
COOL
FREECOOL
PRESSURE
EVAC
VENT
Air Source Supply Air Temp
– Displays the air source's SAT when
Airside Linkage Status
is
Active
.
R:
-56 to 245°F
(-48.9 to 118.3°C)
Air Source Static Pressure
– Displays the air source’s supply static pressure when
Airside
Linkage Status
is
Active
.
R:
0 to 5.0 in wc
(0 to 1.245 kPa)
Air Source Outdoor Air Temp
– Displays the air source’s OAT when
Airside Linkage Status
is
Active
.
R:
-56 to 245°F
(-48.9 to 118.3°C)
VAV Zone Controllers
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