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Trouble-shooting
The supply air fan stops
In the Econo model, the thermostat stops the supply air fan when
the temperature inside the air heater drops to +10 °C (the function
protects the air heater against freezing).
Check that the water circulates in the air heater, and that the water
flows in the correct direction, by touching the surface of the pipes.
The air heater valve is located on the inlet water side and the tem-
perature there should be higher. The piping system should have a
venting valve at its highest point.
You find that you cannot change the fan speed from the
control panel, or the function is unstable
The control circuit cable for the ILTO Premium system including the
connectors is supplied with the ventilation unit. The cable can be
lengthened together with its connector in a 20 mm dia. conduit.
When the cable is drawn through the conduit, the drag line must not
be fastened to the cable, not the connector or come in contact with
the conductors. The control system operates on low safety voltage.
It is not permissible to run mains voltage cables in the same conduit
or next to the control cable conduit.
Check how the connectors are attached and the condition of possible
jointing connectors.
Water collects in the bottom of the ventilation unit
When the outside air is cold, moisture condenses on plate heat
exchanger surfaces in contact with the extract air and condensate
runs towards the extract air side. A connection for drainage is located
on the bottom of the ventilation unit and a water trap is provided
in the hose leading from the drain connection. Water will collect in
the bottom of the unit if the discharge hose becomes clogged or if
there is more than one water trap in the hose (a rise in the direction
of flow upstream or downstream of the water trap, the end of the
hose in water).
Remove the superfluous water trap and check the drainage function
by pouring water on the bottom of the ventilation unit.
You hear a “clicking” noise from the unit at irregular
intervals
The thermostat valve of the Econo model is mounted on the inlet
flow side, which means flow toward the valve disk and the actuator.
If the flow direction is wrong, the flow of liquid to the valve is shut
off at times, and this causes the clicking noise.
Make sure that the liquid is flowing in the right direction.
The supply air diffuser discharges cool air
The water-heated air heater for reheat in the Econo model generates
excess heat, which during cold weather, heats the supply air to the
setting on the thermostat. If the liquid supplied to the air heater isn't
hot enough (the circulation circuit is closed or has not been vented,
the circulation pump has stopped, the temperature setting on the
valve is too low), the supply air from the ventilation unit will be cool.
Check that the water circulates in the air heater, and that the water
flows in the correct direction, by touching the surface of the pipes.
Check the temperature setting on the thermostat (should be set to
position 3 = +20 °C).
In the electrically heated model, an air heater heats the cold sup-
ply air to the setting on the thermostat. The air heater is protected
against overheating with an overheat protection that has to be reset
manually if it has tripped.
Check the setting on the thermostat (18–22 °C). Press in the reset
button of the overheat protection. A click heard when you press the
button indicates that the excess temperature protection has been
reset. Find out the reason why the air heater became overheated
(clogged air filter, clogged external wall grille, the thermostat sensor
by the suction opening of the fan is out of position, the sensor of the
overheat protection is in contact with the surface of the air heater).
The motor of the by-pass damper operates wrong (closes in the
winter and opens in the summer).
Reverse the function by changing the setting of the switch under
the damper motor cover (the switch can be set to position R or L).
If the ventilation unit emits warm air, the thermal insulation on
the pipe system may be insufficient (measure and compare the air
temperatures at the supply air diffusers furthest away and nearest to
the ventilation unit when the outside temperature is below freezing.
The difference should be less than 5 °C).
The heat exchanger freezes
The water that has condensed on the plate heat exchanger freezes if
the temperature on the coldest spot of the heat exchanger is below
0 °C. Freezing is prevented by a temperature-controlled function: The
supply air fan is decelerated and the extract air fan is accelerated if
the temperature by the sensor is lower. The function will return to
normal when the temperature by the sensor rises. The supply air fan
will stop if the temperature by the sensor does not rise.
On the models with infrared detection (optional equipment) there
is a transmitter/receiver by the heat exchanger element’s freezing
point (on the extract air side, about 15 cm obliquely upward from the
outside air connection depth-wise) which indicates ice forming on
surfaces and starts the de-icing function: The supply air fan deceler-
ates and the extract air fan accelerates if the temperature by the
sensor is lower. Operation will return to normal when the infrared
beam connection is re-established. The supply air fan will stop if the
beam connection does not return within a half hour.
Check that the sensor is located at the right spot. When the sensor
hook is fitted (the transmitter diode should be under the support
tube of the hook), check the connection between the transmitter
and the receiver (from the Premium panel).
In models with air heater for reheating (optional equipment), the
infrared sensor switches on the reheating and switches the supply
air fan over to position 1 for at least 20 minutes (it does not stop
completely). The air heater might freeze if its overheating protection
has tripped.
Reset the overheating protection by pressing the button next to the
air heater for reheat. Find out the reason why the air heater has
overheated (the air filters or the external wall grille are clogged).
Check the function by placing something in front of the infrared
sensor (the light goes out).
Содержание ILTO X100 Premium
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