Daikin MPS026 F - Installing Duct Static Pressure Sensor Taps

Installing Duct Static Pressure Sensor
Taps
For all VAV units, duct static pressure taps must be eld
installed and connected to the static pressure sensor 1 (SPS1)
in the unit. Sensor SPS1 is standard on VAV units and is
located in the main control panel.
Carefully locate and install the duct static pressure sensing
tap. Improperly locating or installing the sensing tap causes
unsatisfactory operation of the entire variable air volume
system. Below are pressure tap location and installation
recommendations. The installation must comply with local code
requirements.
1. Install a tee tting with a leak-tight removable cap in each
tube near the sensor tting. This facilitates connecting a
manometer or pressure gauge if testing is required.
2. Use different colored tubing for the duct pressure (HI)
and reference pressure (LO) taps, or tag the tubes.
Daikin recommends 3/16" ID tubing.
3. Locate the duct pressure (HI) tap near the end of a long
duct to ensure that all terminal box take-offs along the
run have adequate static pressure.
4. Locate the duct tap in a nonturbulent ow area of the
duct. Keep it several duct diameters away from take-off
points, bends, neckdowns, attenuators, vanes, or other
irregularities.
5. Use a static pressure tip (Dwyer A302 or equivalent) or
the bare end of the plastic tubing for the duct tap. (If the
duct is lined inside, use a static pressure tip device.)
6. Install the duct tap so that it senses only static pressure
(not velocity pressure). If a bare tube end is used,
it must be smooth, square (not cut at an angle) and
perpendicular to the airstream (see Figure 15).
7. Locate the reference pressure (LO) tap near the duct
pressure tap within the building. If the tap is not connected
to the sensor, unsatisfactory operation will result.
8. Route the tubes through the curb and feed them into the
unit through the knockout in the bottom of the control
panel (see Figure 14). Connect the tubes to appropriate
barbed ttings (on SPS1) in the control panel. (Fittings
are sized to accept 3/16" ID tubing.)
Figure 14: Static Pressure Tubing Knockout Location
Figure 15: Duct Static Pressure Sensing Tubing
Installation
Roof
SPS1
Main Control Panel Condenser Section
HI Line
LO Line
Remote Sense Point
To Sensor
HI Input
Pressure Sensing
Tubing
Tubing Extends
Through Approx. 1/8”
Rubber
Grommet
Ductwork
(Remote Location)
To Sensor
LO Input
meChanICal InsTallaTIon
www.DaikinApplied.com 17 IM 1058-8 • MAVERICK II ROOFTOP SYSTEMS