Locating the Static Pressure Sensor and Probe - Verasys - LIT-12012331 - General System Information - Verasys System - 4.0

Verasys System Changeover Bypass Zoning System Design Application Note

Product
Building Automation Systems > Building Automation Systems > Verasys System
Document type
Application Note
Document number
LIT-12012331
Version
4.0
Revision date
2020-03-24

Locate the static pressure sensor in the correct position to ensure that you can control the bypass damper properly. Figure 1 shows the correct sensor location.

In addition, you must locate the duct static pressure probe in an area where supply plenum pressure is stable. Follow these guidelines when locating the probe:

  • Locate the probe at least 10 ft (3.05 m) downstream from the Air Handling Unit (AHU).
  • Locate the probe at least 5 ft (1.52 m) downstream from the first turn off of the supply plenum trunk.
  • Avoid locating the probe excessively far from the supply plenum trunk or past multiple zone taps.

For a supply plenum tee, locate two probes at least 5 ft (3.05 m) downstream from the main supply trunk on opposing supply plenum branches. Connect the probes with a tee fitting to average the duct static pressure readings from the two supply plenum branches, as shown in the following figure.

Figure 1. Locating Pressure Sensor and Probe in a Supply Plenum Tee

Table 1. Round Bypass Damper Assemblies
Air Velocity through Damper (FPM) Damper Size, in. (Area - sq. ft)
6 (0.188) 8 (0.338) 10 (0.532) 12 (0.769) 14 (1.050) 16 (1.375)
  Airflow (cfm)

1500 FPM - Bypass only

282

507

798

1,154

1,575

2,062

1750 FPM - Bypass only

329

592

931

1,346

1,838

2,405

2000 FPM - Bypass only

376

676

1,064

1,538

2,100

2,749

2250 FPM - Bypass only

423

761

1,197

1,730

2,363

3,094

Table 2. Rectangular Bypass Damper Assemblies
Air Velocity through Damper (FPM) Damper Size, W x H in. (Area - sq. ft)
14 x 12 (0.83) 16 x 16 (1.36) 20 x 20 (2.25) 30 x 30 (5.44)
  Airflow (cfm)

1500 FPM - Bypass only

1,245

2,040

3,375

8,160

1750 FPM - Bypass only

1,453

2,380

3,938

9,520

2000 FPM - Bypass only

1,660

2,720

4,500

10,880

2250 FPM - Bypass only

1,868

3,060

5,063

12,240