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VALLOX DIGIT2 SE/VKL/MLV
© VALLOX • We reserve the right to make changes without prior notification.
PIPE CONNECTIONS
Connection of VKL post-heating radiator to underfloor heating circuit
To minimise the risk of freezing involved in the connection the system has several antifreeze functions.
1. The unit stops if supply air temperature goes below the set temperature and automatically starts as soon as temperature rises.
2. When the unit stops, the self-actuated dampers (E) close.
3. The electric valve (T) opens when the unit becomes dead.
4. The unit issues an alarm of freezing risk at the controller.
Use of VKL post-heating radiator
• The temperature of heating water shall be adjusted according to the temperature of outdoor air.
• No water must be led into the radiator of the unit until the system has been adjusted for operation and the heating network
has heating on or it has been otherwise ensured that the radiator will not freeze.
• Water circulation in the heating network connected to the unit and the circulation pump must not be stopped during the
heating season.
• The base volume of water flow into the radiator of the unit can be adjusted with valves (R), which can also act as stop valves
(not included in the delivery)..
RADIATOR HEATING
R
R
HEAT PUMP
T
UNDERFLOOR HEATING
GROUND COLLECTOR
P
MV
Heating
water
adjustment
Y
E
P
Circulation pump. Size e.g. 0.07 dm
3
/s,
60 kPa, not included in the delivery
Because of the risk of condensing the pump
should be suitable for pumping liquid colder
than the ambient temperature.
MV
Solenoid valve, not included in the delivery.
The valve has to be suitable for the liquid in
the ground collector (e.g. Grundfors UPS-25-
60 180 model K).
T
Valve, included in the unit delivery
Y
One-way valve, not included in the delivery
(as low pressure loss as possible)
E
Self-actuated dampers, included in the
delivery
Connection of MLV preheating/cooling radiator
The radiator is connected to the pipe coming from the ground collector. When the requirements for starting the
heating or cooling function are met, the control function of the unit opens the solenoid valve (MV) and starts the
pump (P).
Observe the frost resistance of the liquid used in the ground collector. Connection pipes of the MLV radiator have
to be insulated against condensation.
Note! Because of the risk of humidity damage, supply air temperature in a duct with no condensation insulation should
not go below +16...20
°
C.
Other connections
Heat can be conducted to the post-heating radiator of DIGIT2 SE VKL in other ways than described above. It is
possible to build a separate circuit for the radiator if higher power is desired, or the risk of freezing can be
eliminated by using non-freezing heat transfer solution. For more information, see the instructions for VALLOX VKL
connections.