8
INTRODUCTION OF THE AIR EXCHANGE SYSTEM
USAGE AND CORRECT LEVEL OF AIR EXCHANGE
The air exchange level is regulated by changing the
working speed of the air impeller from the operating panel.
Airflow of different adjustable positions can be seen
from table 2.
Adjustable position 1 is for basic air exchange for an empty house.
Adjustable position 2 and 3 are normal working positions.
Adjustable position 4 and 5 are efficiency positions (i.e. for saunas).
The correct usage positions will be found by experience;
observing the purity of the air or sultriness when coming in
from outside, observing moisture on the windows or drying
of the sauna.
AFTERHEATING AND SUMMER BYPASS OF INLET AIR
The DIVK-330 DEMA unit is equipped with 2000W electrical
battery operated by the means of triac-adjuster or a water battery
(VKL) operated bythe operating device for afterheating the heat
recovered inlet air.
The temperature of inlet air is usually regulated to +17C.
The temperature may be adjusted to higher during winter so there
would be no draught like feeling. In case of severe frost and
efficiency mode the heating power might turn out insufficient –
in such circumstances, the air exchange should be reduced.
The overheating protection launched during malfunctioning
must be annulled manually.
During summertime, the heat recovery exchanger element
on the bypass platewill be closed so the exhaust air will not
warm up the inlet air.
THE SUMMER BYPASS OF THE UNIT MUST BE IN THE WINTER POSITION WHEN THE AIR FLOWS ARE BEING ADJUSTED
CONDENSING WATER AND FREEZING PREVENTION
As the extract air cools in the heat exchanger, the moisture
condenses into water, which flows into the condensate
pool and from there along the hose through the water trap
to the open drain.
In frosty weather the freezing
of condensate water is prevented by a dual-
acting antifreeze function, which first turns the preheater
on and later switches it off when the temperature rises
above the set value. If the power of the preheater is not
sufficient and the waste air temperature drops below the
"waste air cold" limit, the supply fan power is incrementally
reduced until the "waste air cold" limit value is reached.
MAKE SURE THAT:
- There are no loose objects within the unit or the air impeller;
- The coverings of construction-time are removed from
the outlet- and exhaust air holes;
- All isolations and steam barriers are in order;
- The heat transfer and fans are in their places;
- The condensing water outlet is installed and the water
is drained out;
- The air impellers and their adjusters are in working order;
- Afterheating is regulated and working.
USAGE DURING INSTALLING
The air exchange unit should be started as soon as
installation permits.
Efficient air exchange promotes drying of the constructions
and prevents damage.
In case channelling has not been completed, fans and adjustments
are missing,filter paper must be used in place of fans to keep
the channels clean andprovide sufficient counterpressure for
preventing overload. The unit must be used with full power and
check the drainage of the condensing water.
The appliance, filters and heat exchangers must be cleaned
and the systemadjusted after the construction works are
completed.
BASIC ADJUSTMENT OF AIRFLOW
The unit alone can not produce good interior ear in case
the channels and fans are installed carelessly and main
adjustments are not made.
Regulate the inlet and outlet fans to the planned positions
and start the unit
at design power speed. Measure the airflow in outside- and
exhaust air channels.
The outlet must be 10-25% higher than inlet. Check the
pressure level of thechannels by checking from the fans and
adjust it accordingly to obtain the pressure level of 20-30 Pa
for fans; adjust and lock the pattern.Draw measuring- and
adjustment records!
