VALLOX 90K SC
© VALLOX • We reserve the right to make changes without prior notification.
1.09.347E
/30.8.2006/PDF/Premedia Focus
Vallox Oy FIN-32200 Loimaa T358 2 7636 300 T358 2 7631 539
Internet: www.vallox.com
REASON
• Air cools down in the attic ducts.
• The heat recovery cell is frozen, which is why extract air cannot heat outdoor air.
• The preheating radiator does not work.
• The extract air filter or the cell is clogged.
• The initial adjustment of ventilation has not been done.
DO THIS
• Measure the temperature of supply air in the unit and compare it with the air coming
from the valve.
• Check the insulation of the attic ducts.
• Check the operation of the defrost thermostat and preheating resistor (see section 2.6
“Defrosting” on page 5). You can turn the defrost thermostat clockwise. In this case
there will probably be no freezing, but extract air can be too warm when going out.
The defrost thermostat can also be turned anticlockwise. In this case, the risk of
freezing of the heat recovery cell will increase. According to the factory setting, the
defrost thermostat works at +5
°
C.
• Check that the filters and the heat recovery cell are clean.
• Check the initial adjustment.
1. Outdoor air coming to the dwelling is cold.
REASON
• The heat recovery cell defrost function works and prevents the cell from freezing.
DO THIS
• If you want the fan to stop at temperatures lower than the preset value, you can decrease
the threshold value of the thermostat by 1 to 2
°
C.
NOTE. If you decrease the threshold value too much, the cell may freeze. See item1.
2. Supply air fan keeps stopping
4. TROUBLESHOOTING