AK-CC 750 - 080Z0130 & 080Z0139
RS8GM222 © Danfoss 10-2014
71
Thermostat function
Valve type and thermostat
Principle
Up to 4 valves can be connected to the controller; one for every
solid state output.
It is possible to use electrically controlled expansion valves type
AKV for regulation, or else injection can take place using thermo-
static expansion valves (TEV) in which the temperature is regu-
lated using solenoid valves in the liquid line (LLSV), e.g. Danfoss
type EVR.
The thermostat function can be defined in different ways depend-
ing on which application it is used for. For example:
• regulation principle /
• what sensors are to be used /
• whether the user wishes to toggle between two temperature
settings, etc.
It is necessary for at least one air sensor to be fitted for every evap-
orator section. This is applicable irrespective of which thermostat
function is selected – including "
no
" thermostat. The thermostat's
cut-out temperature also has to be set to the correct air tempera-
ture as this value is used by the injection function.
Thermostat type= ON/OFF
One common valve for all evapo common ON/OFF ther-
mostat
A line up of refrigeration appliances which are to be regulated to
the same temperature is a typical example.
The temperature is controlled according to the ON/OFF principle
in accordance with the thermostat settings in section A.
The thermostat can control the temperature via:
• a signal from the S3/S4 sensors in section A, or
• min/max or average temperatures in all the sections used (see
the section on sensor selection).
AKV valve
This principle can also be used with electronic expansion valves
type AKV; e.g. refrigeration appliances where one valve is used for
two evaporators. These appliances are specially designed for this
application as the evaporator area is divided over two refrigeration
sections in order to achieve a consistent load over the two circuits.
One valve for every evap common ON/OFF thermostat
Here, one valve is used per evaporator and the temperature is
controlled according to the ON/OFF principle in accordance with
the thermostat settings in section A
.
The thermostat can control the temperature via:
• a signal from the S3/S4 sensors in section A, or
• min/max or average temperatures in all the sections used (see
the section on sensor selection).