JOHNSON CONTROLS
56
FORM 102.20-N1
ISSUE DATE: 7/06/2016
SECTION 3 - HANDLING, STORAGE, AND INSTALLATION
AIR MEASURING DEVICE CONNECTIONS
Air Measuring at the Fan Inlets
•
COMETER is a probe attached to the fan bearing
support on Comefri Forward Curve fans from size
7 x 7 up to 18 x 18. The probe is located on the
outboard side of the housed fan assembly. The
probe is piped to the negative (-) port of a factory
mounted transducer on the fan wall. The positive
(+) port is left open to the fan section. Wiring
is not provided to the transducer unless factory
packaged controls were selected.
• PIEZORING (PIEZOMETER) is a fitting or se
-
ries of fittings in the inlet cone(s) of housed fans
larger than 18 x 18 and all sizes of Plenum fans
that are combined into a single connection piped
to the negative (-) port of a factory mounted trans-
ducer on the fan wall. The positive (+) port is left
open to the fan section. Wiring is not provided
to the transducer unless factory packaged controls
were selected.
The fan manufacturer does not recom-
mend placement of the flow measuring
probes inside the fan inlet cone in the
path of airflow. These devices create
disturbances and unpredictable perfor-
mance losses.
FIGURE 82 -
HIGH AND LOW CONNECTIONS FOR
AN IN FAN AIR MONITORING SYSTEM
LD17231
FIGURE 83 -
HIGH AND LOW CONNECTIONS AND
ASSOCIATED TUBING FOR FAN MOUNTED AIR
MONITORING SYSTEM
LD17232
FIGURE 84 -
PORT LOCATIONS FOR FAN
MOUNTED AIR MONITORING SYSTEM
LD17233
High Port
Low Port
Air Measuring at Unit Outside Air Inlets
•
AMS-60 used on Indoor Solution air handlers
usually measure outside air. This can be provided
with one or two pairs of positive (+ or High) and
negative (- or Low) pressure tube connections.
Connect (+) & (-) respectively to the (+) & (-)
ports of the transducer(s). Wiring & transducer
are not provided unless factory packaged controls
were selected.
