Vallox 51 MV, Manual

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© Vallox Oy - All rights reserved
MV
Always follow first and foremost the connection diagram
provided by the HVAC designer or heat pump manufacturer. Also
read the duct radiator manual.
The accompanying figure shows an example of the arrangement
for connecting the heating/cooling radiator unit to the heat
collection circuit.
Connect the radiator output pipe to the heat collection circuit
return pipe. Direct the fluid returning from the radiator unit to
the heat collection circuit return pipe. If you know that there is
a large loss of internal pressure inside the heat pump, the heat
pump should be bypassed. If this is done, the fluid circuit will
come into operation when the heat pump comes to a halt. When
this happens the pressure loss in the one-way bypass valve Y2
must be lower than the pressure loss in the heat pump.
Heating:
The pump starts when the outdoor air temperature
drops below the winter limit value set at the factory (-5 °C).
Cooling
The supply air setpoint value for the active mode (for
example, At home) controls the pump start-up. The pump starts
when the supply air setting is below the temperature of the
supply air that is blown into the apartment.
The duct radiator can be installed in both the supply air duct and
the outdoor air duct. If the radiator is installed in the outdoor
air duct, it can be used for both preheating and cooling. If the
radiator is installed in the supply air duct, it can be used for
heating or for cooling only.
The duct radiator can be set to function either automatically or
manually:
• Automatic
- In summer, the supply air temperature will be
maintained at the level specified in the temperature setting.
In winter, the duct radiator will turn on, when the outdoor
temperature falls below the winter setting.
• Manual
- In summer, the duct radiator will turn on, when
the outdoor temperature rises above the summer setting.
In winter, the duct radiator will turn on, when the outdoor
temperature falls below the winter setting.
To prevent the risk of condensation in the supply air duct, you
can set the adjustment of the supply air limit to automatic or
manual:
• Automatic
- The supply air limit is adjusted automatically
based on the dew point of the extract air. When the supply air
temperature falls too low, the duct radiator will turn off.
• Manual
- The supply air limit can be set manually. When the
supply air temperature falls down to the set value, the duct
radiator will turn off.
If an external sensor is in use, it is selected from the settings of
the external sensor whether it is used to control the outdoor air
duct radiator or the supply air duct radiator. The temperature of
the external sensor can be read from the service menu:
menu >
service menu >
unit information page 5 ”
External sensor
”.
NOTE:
If the duct
radiator is used in
the supply air duct, it
can only be used for
cooling.
NOTE:
When used to
control the outdoor air
duct radiator, the exter-
nal NTC sensor is ins-
talled in the outdoor air
duct before the radiator.
When used to control
the supply air duct ra-
diator, the external NTC
sensor is installed after
the radiator.
NOTE:
When selecting the
relay (C), take account
of the maximum
allowed combined
power supply (6W) of
the circuit board in the
external MV electrical
box, if the relay power
supply comes from the
circuit board’s +24V
connector.
NOTE:
Due to the risk of humi-
dity damage, in a duct
that has not been insu-
lated for condensation
the supply air tempera-
ture must not fall below
+16 … 20 °C.
DUCT RADIATOR OPERATION
TECHNIC
AL SPECIFIC
A
TIONS