AKO 16526A, Руководство пользователя

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3516526A02 Ed. 01
23
Defrost
Types of defrost
There are 5 possible defrost types, depending on the option selected in the wizard (Inl):
Electric (InI=1, 2 and 3) (d7=0)
Defrost is performed through electrical resistors, supplying the evaporator with heat. The operation of fans in this
mode depends on parameter F3; the compressor and solenoid are stopped.
By air (InI=4, 5 and 6) (d7=1)
Usually used in positive cold rooms (> 3°C), since the inside temperature of the cold room is sufficient to melt evap-
orator ice. By default, the fans are activated so that air may circulate through the evaporator; to stop them, change
parameter F3 to 0. The compressor and solenoid are stopped.
Hot gas (InI=7 and 8) (d7=2)
The hot gas from compressor discharge is used to melt evaporator ice and, to this end, two valves are necessary: one
at the condenser input (A) and another between the compressor output and the evaporator input (B).
During the process, the liquid solenoid valve (C) and the condenser input valve (A) are closed and the evaporator
input valve (B) is opened, forcing hot gas to pass through the latter, melting the ice.
Optionally, a high pressure switch (D) can be added to control the solenoid valve (digital input D2, l20=7) during the
defrost process using hot gas. If the pressure decreases, the solenoid opens to allow liquid into the tank; when the
pressure rises again, the solenoid closes.
COND.
EVAP.
A
D
B
C
D1/S3
NO C
Gnd
DIG. IN
E
AUX 3
NO C
FAN
NO C
COOL
NC C
AUX 2
NO NC C
DEF
NO NC C
AUX 1
NO
D2/S4