VALLOX 280 SE
6
INSTRUCTIONS FOR USE
1.13. Heat recovery anti-frost function and preheating
• The anti-frost function prevents the heat recovery cell from freezing, thus ensuring proper
ventilation even during cold periods.
• Anti-frost is implemented by stopping the supply air fan. The stopping function is controlled
on the basis of the measurement data given by the temperature sensor that measures the
temperature of exhaust air after the heat recovery cell.
• The supply air fan stops when exhaust air temperature falls to the setpoint (factory setting
+3
°
C) and starts when exhaust air temperature has risen to the value set (hysteresis setting,
factory s3
°
C).
Preheating (option)
• The unit can be equipped with electric preheating in order to minimise the instantaneous
stopping of the supply air fan. This ensures a maximally even supply air flow through the unit.
• The preheating radiator switches on when exhaust air temperature falls to the setpoint
(factory s5
°
C) and switches off when exhaust air temperature has risen to the value
set (hysteresis setting, factory s3
°
C).
• In order to ensure the operation of the preheating unit, the setpoint of exhaust air temperature
must be higher than that of supply air fan stopping temperature.
1.14. Anti-frost function in a water-circulated post-heating unit
• The anti-frost function aims at preventing a water-circulating post-heating unit from freezing.
The automatic function stops the supply and extract air fans as soon as outdoor air
temperature falls below 0
°
C and supply air temperature below +7
°
C, in which case also
the control valve becomes wide open. The control panel displays the fault message
FREEZING ALERT, irrespective of display.
• The fans start automatically as soon as supply air temperature exceeds 10
°
C.
1.15. Maintenance reminder
• The maintenance timer switches on the maintenance reminder symbol ( ) in the main display
of the control panel at defined intervals, the factory setting being 4 months.
• The maintenance reminder symbol is reset at the control panel (see the instructions for using
the control panel, Section 2.3.10.).
• The interval can be set within the range of 1...15 months at the control panel.
1.16. Filter guard function
• If the unit is equipped with pressure difference switches monitoring the supply and/or extract
air filters, they light up the filter guard symbol ( ) in the main display of the control panel
when pressure has risen above the setpoint. At the same time, the points of the fault signal
relay are closed.
• The operation threshold for a pressure difference switch is adjusted to correspond to the
ventilation power position. The adjustment of the operation threshold can be made at the
controller of the pressure difference switch (see Pressure difference switch setting,
Section 4.1.). The factory setting (275 Pa) corresponds to ventilation power position 8.
• The maintenance timer operates normally during this function.
Pressure difference switch
© VALLOX • We reserve the right to make changes without prior notification.
