Hvac ZP4-ESP, Installation Manual

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SPS Terminals
The SPS terminals 2 and 3 wire to the ZPA-SPS Static Pressure sensor. The sensor should be
installed on a flat surface so that the diaphragm is in the vertical position. Use the 1/4” x 36” tubing
provided and connect one end to the (P1+) high pressure fitting on the sensor. The other end of the
tubing should be connected to the plastic sensing probe mounted in the main discharge air plenum
prior to any zone dampers or duct transitions. The sensing probe is 2-1/8” x 1/4” O.D. Install and
mount the probe with the arrow in the direction of airflow. The pressure sensor is factory set for 0.35”
W.C. but is fully adjustable from 0.08 to 1.2” W.C. The terminals are not polarity sensitive. Use 18-2
thermostat wire. After removing the outer jacket, strip approximately 1/8” insulation off of each wire.
Land the wires to terminals 2 and 3 on the pressure sensor and repeat the process on the other end
by landing the wires to the SPS terminals on thepanel.
NOTE: The ESP function only works with 3-wire, power open / power close dampers.
3 2
FACTORY SET
0.35” W.C. AT STATIC PRESSURE
SETPOINT DIAL
ZPA-SPS
How ESP Works
As zone dampers open and close, the ZPA-SPS Static Pressure Sensor continuously monitors the
system static pressure. If the static pressure goes above the static pressure setpoint, the sensor will
send a signal to the panel which will begin to open selected non-calling zone dampers until the static
pressure setpoint is maintained. The SPS LED will come on until the static pressure reaches setpoint
and then will turn off. Any zone with the bypass jumper in the OFF position will not be allowed to
bleed air. The small amount of air allowed to bleed into selected non-calling zones eliminates air
noise and ensures proper airflow through the HVAC system. This also prevents coil freeze up and
high temperature issues. When all zones are satisfied, all zone dampers will go to the full open
position provided no thermostat is calling for ventilation mode.
CONTROL MUST BE MOUNTED
IN VERTICAL POSITION
THE 1/4” TUBING SHOULD BE
CONNECTED TO P1+
HIGH PRESSURE FITTING ON THE
PRESSURE SENSOR
AIR HANDLER
RETURN
AIR
SUPPLY
AIR
INSTALL
SENSING
PROBE
WITH ARROW
IN DIRECTION
OF AIRFLOW
ZPA-SPS