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LO STAT ∆P setting is the desired airflow limit when the
thermostat pressure is less than, or equal to, the reset start
point.
• For DA Cooling or RA Heating:
Adjust LO STAT ∆P to the desired minimum airflow
with 0 psig (or a pressure less than the reset start point) at
port "T." The LO STAT ∆P must be set first. The LO
STAT ∆P will affect the HI STAT ∆P setting.
• For RA Cooling or DA Heating:
Adjust LO STAT ∆P to the desired maximum airflow
with 0 psig (or a pressure less than the reset start point) at
port "T." The LO STAT ∆P must be set first. The LO
STAT ∆P will affect the HI STAT ∆P setting.
HI STAT ∆P setting is the desired airflow limit when the ther-
mostat pressure is greater than, or equal to, the reset stop-point.
The reset stop-point is the reset span pressure added to the
reset start-point pressure.
• For DA Cooling or RA Heating (see Fig. 6):
Adjust HI STAT ∆P to the desired maximum airflow with
20 psig (or a pressure greater than the reset stop point) at
port "T." The HI STAT ∆P must be set last. The HI STAT
∆P setting will be affected by the LO STAT ∆P setting.
• For RA Cooling or DA Heating (see Fig. 6):
Adjust HI STAT ∆P to the desired minimum airflow with
20 psig (or a pressure greater than the reset stop point) at
port "T." The HI STAT ∆P must be set last. The HI STAT
∆P setting will be affected by the LO STAT ∆P setting.
NOTE: After the "LO STAT ∆P" and "HI STAT ∆P" initial
adjustments are made, cycle the thermostat pressure a few
times to settle the internal reset mechanisms and verify set-
tings. Fine tune the settings if necessary. The thermostat pres-
sure may be left at a high pressure and the "G" port cap may be
removed and replaced to cycle the reset mechanism.
RESET START setting is factory set at 8.0 psig. This is the
lowest thermostat pressure that the LO STAT ∆P airflow will
begin to reset towards the HI STAT ∆P airflow. To change the
RESET START setting; regulate thermostat pressure to the "T"
port to the desired reset start point pressure, adjust RESET
START adjustment until pressure at the "G" port is slightly
higher than 0 psig, i.e., 0.1 psig.
NOTE: The "G" port taps into the controller's internal reset
chamber, which always starts at 0 psig. The RESET START
PROBLEM
Controller does not reset to maximum or minimum set point during bal-
ance procedure.
Controller does not reset to maximum or minimum set point during
operation.
Pneumatic actuator does not stroke fully.
Air valve stays in wide open position.
NOTE: Always check:
• Main air pressure (15 psi to 25 psi) at the controller.
• Disconnected or kinked pneumatic lines to the controller.
• Quality of compressed air (oil or water in lines).
adjustment is a positive bias adjustment that sets the desired
thermostat start point to the controller's internal reset start
point of 0 psig.
RESET SPAN setting is factory set at 5.0 psig. This is the
required change in thermostat pressure that the controller will
reset between the LO STAT ∆P setting and the HI STAT ∆P
setting. To change the RESET SPAN setting; adjust RESET
SPAN adjustment until pressure at the "G" port equals the
desired reset span pressure.
NOTE: The "G" port taps into the controller's internal reset
chamber, which will always be at a pressure between 0 psig
and the RESET SPAN pressure.
Preventative Maintenance
1. Inspect pneumatic tubing for loose connections or leaks.
2. Clean out pneumatic line filters regularly according to
manufacturer's recommendations.
Pneumatic Control Troubleshooting —
DA HEATING
MAX
F
L
O
W
MIN
0
ROOM TEMPERATURE
RA HEATING
MAX
F
L
O
W
MIN
13
ROOM TEMPERATURE
*May require changing the RESET START from 8.0 to 3.0 psig if
sequencing is involved.
Fig. 6 — Reset Cycle for CSC-3011 Control
Table 7 — Troubleshooting
Balancer is using the thermostat for control signal. An artificial signal
must be provided in place of the thermostat.
Thermostat is not demanding maximum or minimum air volume. Main
air pressure at the controller is less than 15 psi.
Leak in pneumatic line between the controller and the actuator. Main air
pressure at the controller is less than 15 psi. Leak in the diaphragm.
Velocity probe is blocked by an obstruction (sandwich bag, etc.). Insuffi-
cient supply air in the inlet duct.
• Proper thermostat signal and logic (Direct/Reverse Acting).
• Blocked velocity probe or insufficient primary supply air.
• Leaks in the actuator diaphragm.
• Mechanical linkage of the actuator/air valve.
8
Reset
MAX
Span
LO STAT ∆P
F
L
O
W
HI STAT ∆P
MIN
3
8
13 psig
∆
Reset Start*
ROOM TEMPERATURE
Reset
MAX
Span
HI STAT ∆P
F
L
O
W
LO STAT ∆P
MIN
8
3
0 psig
∆
Reset Start
ROOM TEMPERATURE
PROBABLE CAUSE
See Table 7.
DA COOLING
Reset
Span
HI STAT ∆P
LO STAT ∆P
0
3
8
13 psig
∆
Reset Start
RA COOLING
Reset
Span
LO STAT ∆P
HI STAT ∆P
8
13
3
0 psig
∆
Reset Start*
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Table of Contents
Troubleshooting
