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VAV-SVX02B-EN
Use the following procedure to set-up the PVR:
1. Select damper action (NO or NC). Loosen damper selection switch screw and align to either the NO or NC pointer with damper
pointer and tighten screw.
2. Now determine the type of thermostat that will be used. If a direct-acting thermostat is used, the reset start pressure is ty pically
8 psi. If a reverse-acting thermostat is used, the reset start pressure is typically 3 psi (see Figure 11).
3. With an accurate gage (0-10 psi) connected to port “G”, regulate the thermostat pressure to port “T” to desired start point pressure.
4. Adjust reset start to indicate 0 psi on port “G” and continuing adjusting to indicate a pressure slightly higher than 0 psi, (i.e., 0.1 psi).
Model 3011—Pneumatic
Volume Regulator
Adjusting the Reset Span (3011)
The reset span is factory-set at 5 psi. This is the thermostat pressure difference from which the PVR delivers flow from minimum
to maximum setpoints. This range is not normally changed unless a special control scheme is used where control operation
must be changed.
To field adjust a different reset span, follow these steps:
1. Connect an accurate gage to port “G”.
2. Apply 20 psi to port “T”.
3. Adjust reset span to indicate the desired span on port “G” (see Figure 12).
4. LO-stat and HI-stat delta P must now be readjusted (see following calibration procedure)
Figure 12– Adjusting Reset Span
Figure 11–Adjusting Reset Start
I N
C R
Adjust to obtain 0–0.1 psi at port G
I N
C R
NO
N
C
M
B
DAMPER
G
RESET SPAN
HI STAT
∆
P
LO STAT
∆
P
RESET START
psi
0
10
Connect Hand Pump
0–20 psi
Handpump
Input desired LO stat
pressure at t-stat port
Connect 0–10 psi Gage
Factory-set at 5 psi
Adjustable (0–10 psi)
NOTE: The arrows on the damper selector must be aligned
exactly or the range of the controller will be limited .0 psi
CR
C
C
10
0
PSI
DAMPER
NO
M
B
H
I N C
C
G
N
C
Adjust to obtain desired reset span
Apply 20 psi
RESET START
LO STAT
RESET SPAN
R
R
R
CR
R
I N C
C
HI STAT
P
T
P
P
