Hotgas Regulation; Thermostat Function; Definition Of Thermsotat Function - Danfoss ADAP-KOOL AKC 114 G Mode D'emploi

Hotgas regulation

Thermostat function

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The thermostat function can be defined in various ways depending on the regulation principle,
the sensors to be used, whether there is to be night operation, etc. It is a requirement that one
air sensor must always be mounted. This applies no matter which thermostat function is
selected - even if no thermostat function is required. It is likewise a requirement that the
thermostat's cutout temperature ("CutOut°C") is set at the correct air temperature, as the value
is used by the injection function.
Definition of thermostat function:
You may choose between two thermostat functions:
ON/OFF thermostat
1. ON/OFF thermostat
- The controller compares the air temperature measured with the set and when the air
temperature drops to the cut-out value, refrigeration is stopped. (The expansion valve is
closed).
- The air temperature is measured with the relevant sensor (see later).
3. Modulating thermostat function
- Cutout value and differential are set as for an ON/OFF thermostat.
- The air temperature is measured with the attached sensor (see later).
Principle
When products are initially cooled down and in connection with major load variations
where the temperature has been outside of the differential zone, regulation is carried out
according to the MSS principle.
At stable loads the thermostat will reduce the AKV valve's opening time, so that the flow of
refrigerant will be limited to exactly the quantity that is needed to keep the temperature at
the required reference value.
The reference temperature will be set as the cutout temperature plus half the differential.
Melting function
Only for control of refrigeration (-5 to +10)
The function will ensure that the evaporator is not blocked by frost.
This function operates once an hour, and the frost that has settled on the evaporator will then
melt to water (or to ice, if there is a lot of frost). This ensures a better air flow through the evaporator
at the same time as the insulating effect of the frost disappears.
Function description RC.8A.R1.02 © Danfoss 10/2001
Modulating thermostat
AKC 114G