2
Vallox
121
MC
© VALLOX • We reserve the right to make changes without prior notice.
What the units include can vary depending on the sales area.
Adjustment of supply air temperature
and summer/winter function
The temperature of air coming to the dwelling can be adjusted between circa +10 °C and
+30 °C. The midpoint of the adjustment range is circa +20 °C. When supply air temperature
adjustment has been turned in the OFF position, post-heating is not active. This means that
summer function is activated for the ventilation unit. The unit has a motorised summer/winter
function. When the summer function is on, the heat recovery cell is bypassed as soon as outdoor
air temperature has risen above +14 °C. When outdoor air temperature goes below +12 °C,
the unit starts to recover heat. When supply air temperature adjustment is in the AUTO position,
automatic function is activated for the unit. In this case, the setpoint for post-heating is +17 °C
and the heat recovery cell is bypassed automatically according to outdoor temperatures as
indicated above. When the unit bypasses the heat recovery cell, in which case summer function
is activated, post-heating is off.
Fireplace switch function
It is possible to connect a timer-operated switch to the unit. The switch stops the extract air fan
during the time when the fi replace is heated. NOTE! The starting of the extract air fan may
weaken draught in the fi replace! In winter, this situation may disturb the winter function of the unit.
The situation will normalise in a while, after the fi replace function stops.
Winter function of ventilation unit
A threshold value has been set at the factory for the freezing of the heat recovery cell. When the
threshold is exceeded, the ventilation unit starts to melt the heat recovery cell. Melting is done
by stopping the supply air fan.
A normal melting period takes from 15 to 45 minutes depending on the extent of ice on the heat
recovery cell and on the amount of extract air fl ow.
The unit has two different choices for the winter function. One choice is meant for very wet
conditions (for instance swimming hall) and the other for normal operation in dwellings and
detached houses.
The factory setting is normal winter function for dwellings and detached houses.
Adjustment of the relationship between supply and extract air
This feature may be useful when adjusting air fl ows at the valves during mounting. After the
valves have been adjusted, a user does not need, and must not, touch the adjustment. When
needed, supply or extract air fl ow can be reduced at the potentiometer. When the potentiometer
is approximately halfway, supply and extract air fl ow have not been reduced. Turning the
potentiometer anticlockwise reduces the air fl ow on the supply side, and turning it clockwise
reduces the air fl ow on the extract side.
Maintenance reminder
The unit reminds of the need for maintenance every six months if an indicator (not standard) has
been connected to the connectors of the fault signal relay. The indicator then blinks at one-second
intervals. The maintenance reminder is reset when the door of the ventilation unit is opened. See
the maintenance instructions for information on the necessary maintenance activities.
Fan speed adjustment
The fan speed of Vallox ventilation unit can be controlled with a control switch (option), with
a separate cooker hood (option) or directly with a 0-10 V voltage signal.
Speeds 1, 2, 3 and 4 can be selected at the control switch:
1. Operation during absence. When the dwelling is empty, ventilation can be reduced
temporarily.
2–3. Normal operation. In normal operation, air has to be replaced once every two hours.
4. Boosted operation. Cooking, taking a sauna bath, washing, drying clothes, using the
toilet, having guests or a corresponding situation may cause a need for higher ventila-
tion than in normal operation.
OPERATING INSTRUCTIONS
Four-step control switch
(option)
Cooker hood PTXPA-SC
(option)
Adjustment of supply
air temperature
Supply and extract
air fl ow adjustment
potentiometer
Fireplace switch, fl ush
mounting (option)
This appliance can be used by children
aged from 8 years and above and
persons with reduced physical, sensory or
mental capabilities or lack of experience
and knowledge if they have been given
supervision or instruction concerning
use of the appliance in a safe way and
understand the hazards involved.
Children shall not play with the appliance.
Cleaning and user maintenance shall not
be made by children without supervision.
