NuAire CVD125 Installation And Maintenance

1.0 Introduction
This constant volume damper is designed for installation with
Nuaire's range of fans.
Units are rectangular in section, manufactured from galvanised
steel.
The CVD damper will control the flowrate passing through it when
the pressure drop across the damper is within the range stated in
the performance envelope.
Two flow settings are available; trickle and boost. The damper will
operate in the trickle setting when it is powered up and will go into
the boost setting when a mains signal is received at the SL terminal
or when the CVD-PIR (optional ancillary) is activated. A run-on timer
(adjustable between 1 to 60 minutes) will hold the damper in the
boost setting for the preset time period.
2.0 Dimensions
Plan view
Airflow
Side view
Dimensions in mm.
Code A B
CVD125 300 180
CVD150 300 200
CVD200 300 230
3.0 Handling
Handle the units carefully to avoid damage and distortion to
moving parts.
4.0 System Design
A nominal pressure drop must be allowed in order to ensure
adequate airflow through the damper. To ensure the airflow
pattern through the damper produces consistent readings; the
pressure drop across the damper should not exceed the
recommended value. Recommended values are listed in the table
following and show the performance envelope of each damper.
Nominal design pressure is the value needed to produce the
maximum rated airflow for the damper. If the desired flowrate
is less than the maximum, a lower design value may be used
by reading off the lower curve of the appropriate chart. Please
allow 40Pa (min).
Nuaire: A Trading Division of Polypipe Limited Western Industrial Estate Caerphilly United Kingdom CF83 1NA
T: 029 2088 5911 F: 029 2088 7033 E: info@nuaire.co.uk W: www.nuaire.co.uk
CVD125/150/200
Constant Volume Dampers
Installation and Maintenance
Figure 1.
A
F
C D E F kg
195 125 75 400 3.5
220 150 90 400 3.7
275 200 115 400 4
Model code Nominal design
pressure drop
CVD125 70Pa
CVD150 80Pa
CVD200 90Pa**
*recommended maximum operating pressure to ensure the damper
would work within calibration limits.
Keep the duct velocity as low as possible to ensure the system
produces the lowest energy usage, preferably below 5m/s.
**Allow 90Pa for duties below 100l/s and 150Pa for duties between
100l/s and 125l/s.
Figure 2. Performance envelope for CVD125.
180
160
140
120
100
80
60
40
20
0
0 10 20
Figure 3. Performance envelope for CVD150.
250
200
150
100
design pressure
50
0
0 20
Figure 4. Performance envelope for CVD200.
300
250
200
150
Nominal design pressure
100
50
0
0 20 40
*Allow 90Pa for duties below 100l/s and 150Pa for duties between
100l/s and 125l/s.
1
The EMC Directive
2014/30/EU
The Low Voltage
Directive
2014/35/EU
Maximum pressure
across damper*
140Pa
160Pa
200Pa
design pressure
30 40 50
Volume flowrate l/s
40 60 80
Volume flowrate l/s
*
60 80 120
100
Volume flowrate l/s
10. 05. 17. Leaflet Number 671638
60
100
140 160