Q & A For Heat Exchange Ventilators - Toshiba VN-250SE Service Manual

12. Q & A FOR HEAT EXCHANGE VENTILATORS
Question
u Fan does not operate.
u Fan does not ventilate
(suction air).
u Drop of heat exchange
effect
u Water drops on the
ceiling surface.
u Dew condensation
generates on surface of
the main unit.
•
Is the electric wiring securely performed?
For this model, the terminal block for connection of cables is provided
to the side of the main unit. The connecting works between the power
supply and the switch and between the switch and the main unit are
performed by the special dealers. Incorrect cabling from the specified
switch and the switches disables to adjust the air volume. Therefore,
check the cable connection.
•
Are not the various filters clogged with dust, etc.?
Perform cleaning described in Owner's Manual.
•
Is not the heat exchanger clogged with dust, etc.?
Especially in case that the mounting direction of the product is incor-
rect (indoor side and outdoor side), dust, etc. is clogged in a short time
because the indoor air and outdoor air do not pass through the filter but
flow directly in the heat exchanger.
SA
indoor side
RA
•
Does not generate the dew condensation on the heat exchanger?
In the heat exchange, the temperature difference between indoor and
outdoor is widened. Therefore, in the heat exchanger, the dew condensa-
tion generates according to some conditions of temperature and humid-
ity, and the dew condensation/freezing generates according to some
conditions of outdoor air. In these cases, the status returns to the original
status when temperature of the outdoor air ascends and thaws. For the
measures, heating of air at low-temperature side is necessary as de-
scribed in Installation Manual.
•
Are thermal insulation process applied to 2 duct pipes (Air suction
OA and air discharge EA) at outdoor side?
Be sure to apply thermal insulation because the temperature difference
between indoor and outdoor is widened and the dew condensation may
generate according to some conditions of temperature and humidity.
•
Is the product installed horizontally?
If the product is slanted, various troubles may be caused.
•
Is not the ventilator operated with the normal ventilation in the
winter season?
If the ventilator is operated with the normal ventilation in the winter
season, the surface of the main unit is cooled with the outdoor air
resulting in dew condensation on the surface.
– 29 –
(Users are responsible for the following contents.)
Answer
OA
Outdoor (Out air) side
EA
Air flow