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7.4
Electrical heater
The casing is made of Aluzinc-coated sheet steel, AZ 185,
that conforms to the requirements for corrosivity class C4.
The heater elements are made of stainless steel to EN
1.4301. The junction box includes the terminal blocks
necessary for the electrical connections. The electrical
heaters are produced to degree of protection IP43, but
are also available to IP55 of IP65 to special order. The
heaters are adapted for max 50°C outgoing temperature
and min. air velocity of 1.5 m/s.
All heaters have at least two overheating protections –
one with automatic reset and one with manual reset. All
duct heaters have the overheating protection reset button
on the heater cover.
A built-in regulator ensures simple installation, e.g. due to
fewer cable runs, which lowers the installation cost and
reduce the risk of incorrect wiring. The regulator is
electronic and controls the output across a triac by means
of time proportional control (intermittent ON/OFF
control). This provides very accurate temperature control.
Since control is electronic, it is entirely silent and sustains
a minimum of wear. On heaters with higher ratings, part
of the output are controlled by a step controller. However,
fine adjustment of the temperature is always carried out
by the electronic ON/OFF control.
Control by means of built-in regulator for 0…10V control
signal.
Follow the special instructions of the manufacturer!
Important
• Slowing down time, to avoid radiant heat.
7.5
Counter flow plate heat exchanger
MAXK I3 2000-7000 DC models are equipped with a
highly efficient, counterflow heat exchanger. The counter
flow heat exchanger is equipped with a 100% bypass.
This means that a damper is covering the counter flow
heat exchanger during deicing.In summer there is no
undesirable heat recovery. Plate material of non-
corroding aluminum alloy. Required supply air
temperature is therefore normally maintained without
adding additional heat. The operation of the heat
exchanger is automatic and depends on the set
temperature. The heat exchanger is removable for
cleaning and maintenance. After a long time of use dust
may build up in the exchanger and block the airflow. It is
important to clean the exchanger regularly (once a year)
to maintain high efficiency. The heat exchanger can be
taken out of the unit for maintenance. Wash in hot soapy
water or use pressure air. Do not use detergent containing
ammonia.
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