Airedale StoreMaster 50kW - 77kW - Manual (Page 34)

STOREMASTER
™
Comfort
34
Comfort Range
Technical Manual : 6678403 V1.3.0_ 02_2013
Performance Data
FAN PERFORMANCE - RETURN AIR
Input voltage signal The input voltage signal to the fan speed controller from the unit microprocessor (Vdc) sets
the fan speed for design performance.
The voltage can be determined from the graphs at design air volume using the Total
Static Pressure:
ESP IP TP
 
Where:
TP
= Total static pressure
IP = Internal unit static pressure at 0Pa ESP
ESP = External static pressure at design conditions
Internal static pressure The IP at 0Pa ESP can be determined at design air volume using the system lines
provided on the graphs:
1 = 0 Pa ESP - 100% Free Cooling
2 = 0 Pa ESP - 0% Free Cooling
Select the correct internal system line for the chosen design, (recommended design set up
at 100% free cooling operation).
Example STM50
Air volume, design = 2.7 m³/s
External static pressure, design = 32 Pa
Internal static pressure, from graph = 48 Pa at 100% free cooling
Total static pressure, calculate
= 32 + 48 = 80 Pa
Input signal voltage, from graph = 5.1 V
S
tat
ic
P
res
s
ure (
P
a)
0
20
40
60
80
100
120
140
1.50 1.75 2.00 2.25 2.50 2.75 3.00 3.25
80
1
2
3V
4V
5V
6V
8V
40
D
e
s
ig
n
E
S
P
2.75
Air Volume m³/s
Design Return Air
Volume In line with current building guidelines on air quality, the return air volume has been
designed to provide a maximum of 90% of the supply air volume, thus ensuring a
constant 10% fresh air demand.