Product Overview
Table Of Contents
© Danfoss | DCS | 2019.04
Data sheet | Superheat controller type EKE 1A, EKE 1B, EKE 1C
DKRCC.PD.RS0.A4.02 | 68
ID Symptom Possible cause / Reaction Solution
12 Takes too long to settle
SH at reference point
Too low gain Kp and KpTe or long integration
time Tn.
• 1.Increase Kp by factor of 1.5.
• 2. Decrease Tn 25% of the set value.
• Perform 1 and 2 in loop if needed.
At start up, the pull down time for SH or
temp. is longer.
• Use start with P - control and increase start OD.
• If the superheat in general is 4K higher than reference 1 minute
after start up , the startup OD can be adjusted to be 20 % higher.
Wrong selection of the valve. • Check the valve type and its setting.
Wrong selection of the reference point. • Correctly dene the min, max SH setting and/or reference type
i.e MSS/Load dened ap / Fixed/delta Temp.
• Also check section , High superheat and ‘Too high and too low
superheat’
13 Start up problem Low pressure cut out at start up. • Check the LED Alarm connection.
• Missing synchronization with controller and the compressor i.e.
DI not connected to EKE.
• Wrong or missing valve connection, Check the M12 cable
connection to the valve and to the controller.
• Check other component in the suction or liquid line for any kind
of blockage.
• Use the LOP feature during start up.
Unsynchronized signals. • Make sure that main switch signal and the compressor start are
synchrony, it ok to have until 2 sec delay.
High Superheat after startup. • Check section Too high or too low superheat.
14 Startup problem after
defrost
Low suction cut out • Use EKE defrost sequence feature.
• Use LOP feature.
• Use P- control at start method and prolong the start time.
• Check the right signal from the controller.
15 Unable to maintain
media temperature
Lack of sub-cooling ahead of expansion valve. • Limit max. opening degree of the valve setting in controller.
• Check refrigeration system capacity and compare with expansion
valve capacity. Use proper valve size suitable for the system.
Check section High superheat, and Low
suction pressure.
Wrong selection of temperature sensor and or
installation.
• Check for the right sensor conguration.
Check Working condition of the unit • Check Superheat.
16 Flash gas Loss of refrigerant or undercharge of
refrigerant.
• Charge the system with appropriate refrigerant capacity.
• Check for leakage in the system.
• If the valve is placed much higher than condenser outlet, check
pressure dierence.
Flash gas can lead to high SH or low suction
pressure.
• use the right valve size.
• Also refer to section “High Superheat” and “Suction pressure too low”.
Pressure drop across lter. • Check and replace the lter.
17 Stepper valves open /
close too slow
Incorrect selection of valve type. • Dene the correct valve type.
Incorrect valve installation. • Check the physical valve and cable and install it in right way.
MOPD is higher than valve specication. • Check the valve spec and choose the correct valve.
Check valve speed setting. • Drive the stepper valve with the recommended Speed.
• Too high or too low speed could result in loss step in the valve.
• For the user dened valves, check the other valve settings such as
current, duty cycle, holding current and other relevant parameter.
17 Opening degree of valve
at maximum OD for
longer time period
Lack of cooling capacity. • Check the cooling capacity in the system Also check section,
expansion valve too small.
The condenser pressure is too low. • Check the ambient temperature.
• Adjust the condenser controller.
The lter drier is blocked by dirt. • Replacement Filter drier.
Flash gas in liquid line due to loss of
refrigerant or undercharge of refrigerant.
• Check section Flash gas.
Wrong valve settings. • Check valve setting matching installed valve.
Pressure transmitter is wrongly dened or
selected wrong type.
• Check pressure range and correct pressure
• transmitter type.
Wrong refrigerant selected. • Choose the correct refrigerant in the controller.