UAB AMALVA we reserve the right to make changes without prior notice
10
EN
V2-C5-15-03-v1
¨32
ØDSa
ØLA
Ø32
w
p
∆
–
+
2. VERSO AIR HANDLING UNITS CONSTRUCTION
2.1. Fans
VERSO air handling units are equipped with radial fans with direct drive.
Motors of the fans with backward curved blades must be controlled by
frequency converters. Frequency set by the frequency inverter cannot
exceed frequency data specified in the print out.
Note:
fan type is specified in the print out.
Measuring device for determining air volume
The differential pressure compares the static pressure in front of the inlet ring
with the static pressure in the inlet ring of the narrowest point.
The differential pressure between the static pressures is related to the air vol-
ume via the energy conservation rate as follows:
w
p
k
∆
⋅
=
∇
where k takes
into account the specific ring characteristics.
Example: If differential pressure of 700 Pa is measured for size 630, the air flow
rate can be calculated:
10080
700
381
=
⋅
=
∆
⋅
=
∇
w
p
k
(m
3
/h).
Cleaning and Inspection of Fans and Fan Space
Polluted fans decrease efficiency.
Before performing any inspection work, check whether the unit is switched
off from the electric power supply.
Inspect and clean the fan impellers to remove possible dirt deposits. Check the impeller to make sure that it is
not out of balance. Clean or brush off the fan motor. It can also be cleaned by carefully wiping it with a damp cloth
that has been dipped in a solution of water and dishwashing detergent. Clean the fan space, if needed.
2.2. Plate Heat Exchanger in VERSO-P/PCF Air Handling Units
When operating the air handling unit equipped with the plate heat exchanger, unit control automation should have
function of protection from frost.
Condensate can accumulate in a plate heat exchanger; therefore it is essential to install siphons on the con-
densate drainpipes. Depending on the unit construction, plate heat exchanger section may have 1 or 2 siphones.
It is important to maintain cleanliness of the plate heat exchanger: to
change filters installed in the air handling unit on time, if the heat exchan
-
ger gets dirty, to perform heat exchanger periodical cleaning. The temper-
ature effectiveness of a dirty heat exchanger can diminish considerably.
Fan
Coefficient – k
Fan
Coefficient – k
AC
EC
AC
EC
RH22C
47
-
RH45C
197
240
RH25C
60
70
RH50C
252
281
RH28C
75
93
RH56C
308
348
RH31C
95
116
RH63C
381
438
RH35C
121
148
RH71C
490
545
RH40C
154
188
RH80C
620
-
