CCO
kit
2
Swegon reserves the right to alter specifications. 19/03/2021
2-10 V modulating:
• 2-4.1 Cooling
• 4.1-7.2 Neutral mode
• 7.0 Service mode
• 7.2-10 Heating
Cooling in
Return pipe, chilled water
Supply pipe, heated water
Return pipe, heated water
Return pipe from coil
Supply pipe to coil
From max. to min. heating
Narrow left position = closed for service
Wide right position = neutral
From min. to max. cooling
Technical description
Use
Changeover valve for regulating the heating and cooling
water flow in products such as climate beams and comfort
modules and radiation panels.
The valve supplies the above product with heated or
chilled water which means that the whole product’s heat
exchanger can be utilised and only one actuator with
valve is required.
Function
The valve can be regulated using a 2-10 V motor, which
turns it through 90°.
• At 2 V, the valve is at one of its end stops and fully
open for cooling.
• When the cooling requirement is less, the voltage
signal is increased to close the valve completely at 4.1 V.
• In the range between 4.1 and 7.2 V, the valve is in the
neutral mode (also see neutral mode below).
• At 7.0 V, the valve is closed in service mode.
• At 7.2 V, it begins to open for heating, and at 10 V is
fully open for the flow of hot water.
Neutral mode
The valve is equipped with a pressure equalisation channel.
This prevents pressure differences occurring between the
product and system.
(V)
10
7,2
4,1
2
100-0%
0-100%
q(%)
Cooling
Heating
Neutral
Service
Water quality
Swegon recommends water quality according to VDI 2035-2
for both the heating and cooling system. It is recommended
to install a vacuum degasser to be able to keep the oxygen
content in the water below the levels (<0.1 mg/l) prescribed in
VDI 2035-2, especially in the cooling system where it is harder
to remove loose gas. It is also important that the pre-pressure
in the expansion vessel is dimensioned according to EN-12828
for both the heating and cooling system and that regular checks
of the pre-pressure are made. The cooling and heating systems
are to be deigned to prevent oxygen from entering the system,
this is particularly important to consider when it comes to the
selection of flex hoses, pipes and expansion vessels. When the
system is filled with fresh water, it has an oxygen content of
approximately 8 mg/l, however, this oxygen is consumed quickly
within a few days through corrosion processes. It is then important
to avoid filling the system unnecessarily with new fresh water.
Automatic air vents are usually installed to facilitate the filling
of the system, it is, however, recommended that automatic air
vents are switched off when the system is fully vented to avoid
these sucking air into the system if the pre-pressure in the
expansion vessel drops.
