Danfoss OPTYMA Control

Questions and Answers

J
Jennifer MillerAug 15, 2025
Why Danfoss OPTYMA Control Controller compressor doesn’t start and the display is OFF?
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  millerjeffreyAug 15, 2025
  If the Danfoss Controller compressor doesn’t start and the display is off, check for a power supply issue by ensuring the display on the panel and the plant in operation green light are on. Inspect the ambient probe connections, and replace the sensor if the problem continues. Also, examine the general and auxiliary circuits for tripped breakers; before resetting them, check for short circuits and any absorption anomalies. Finally, verify the secondary circuit protection fuse on the transformer; replace it with a Glass fuse 10x20 F250mA 250V if necessary, ensuring the transformer's secondary absorption doesn't exceed 0.25A and that no extra devices are connected to the Kriwan power supply terminals, and confirm there are no short circuits on the secondary circuit.
K
kathleenwhiteAug 18, 2025
What to do if Danfoss OPTYMA Control compressor doesn’t start?
- B
  bwallaceAug 18, 2025
  If the Danfoss Controller panel is in standby mode (indicated by a flashing green light), reactivate it by pressing the key until the green light is steady. Also, check the electrical connections, calibrations, and proper functioning of the sensors and the compressor. If this is the initial startup, verify the presence of the "PumpDown / Thermostat" operating mode selection bridge on terminal board X1. Jumper the consent terminals of any devices not present in the system, such as Pressure Switches or Kriwan.
M
marywilliamsAug 21, 2025
Why is my Danfoss Control Unit showing a maximum temperature alarm?
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  Frank PerryAug 21, 2025
  If the temperature inside the cold room has exceeded the maximum temperature alarm setting, and your Danfoss Control Unit is showing a maximum temperature alarm, it may be due to the sensor not reading the temperature properly or the compressor start/stop control not working. Check that the compressor is working properly.
K
kandrewsAug 25, 2025
What to do if the Danfoss Control Unit displays an open door alarm?
- S
  Sheila RobertsAug 26, 2025
  If your Danfoss Control Unit displays an open door alarm, check the door switch status and the door switch connections. If the problem persists, it is recommended to contact the technical assistance service.
M
mfarrellAug 27, 2025
What to do if my Danfoss Control Unit compressor protection tripped?
- D
  Diane FowlerAug 27, 2025
  If the compressor protection has tripped on your Danfoss Control Unit, which deactivates all outputs except the alarm one, check that the compressor is working properly and check compressor absorption. If the problem persists, it is recommended to contact the technical assistance service.
A
Amy KingAug 30, 2025
What to do if my Danfoss Control Unit has a cold room temperature sensor malfunction?
- K
  Karla HillAug 30, 2025
  If the cold room temperature sensor on your Danfoss Control Unit is not working properly, check that it is functioning correctly. If the problem persists, replace the sensor.
M
melissa41Sep 2, 2025
What to do if the Danfoss Control Unit defrost sensor is not working?
- E
  Eric NorrisSep 2, 2025
  If the defrost sensor in your Danfoss Control Unit is not working properly, resulting in defrosts lasting the time d3, check that the defrost sensor is working correctly. If the problem persists, replace the sensor.
W
Wayne CopelandSep 6, 2025
What to do if my Danfoss Control Unit displays an EEPROM alarm?
- M
  moorejamesSep 6, 2025
  If your Danfoss Control Unit displays an EEPROM memory alarm, which deactivates all outputs except the alarm one, switch the unit off and then back on.
A
Ashley HolmesSep 8, 2025
What to do if my Danfoss Control Unit triggers a cell light alarm?
- J
  Jessica GarrisonSep 8, 2025
  If your Danfoss Control Unit triggers a cell light alarm because the light of the cell has been on for longer than the set time (tdo), turn off the light.
T
Tony MontoyaSep 12, 2025
How to reset man in cold room alarm on Danfoss Control Unit?
- A
  Adrienne WadeSep 12, 2025
  To reset the 'man in cold room' alarm on your Danfoss Control Unit, reset the alarm input inside the cold room.

Summary

Introduction

General

Overview of the OPTYMATM Control three-phase controller for refrigeration systems.

Technical Characteristics

Product ID Codes

Identification codes for OPTYMATM Control (4 HP and 7.5 HP) electrical panels.

Product Series - Technical Characteristics

Detailed technical specifications for OPTYMATM Control (4 HP and 7.5 HP).

Overall Dimension

Physical dimensions of the OPTYMATM Control electrical panel.

Identification Data

Information on the device tag showing identification data like manufacturer and serial number.

Transport and Storage

Guidelines for safe transport and storage of the electrical panel.

Functionality

Functions Managed by the AK-RC 113 Electrical Panel

Overview of the functions managed by the AK-RC 113 controller.

Installation

Standard Equipment for Assembly and Use

List of standard equipment included with the AK-RC 113 electrical panel.

Mechanical Assembly of the Panel

Step-by-step guide for the mechanical installation of the electrical panel.

Electrical Wirings

Guidelines and precautions for making electrical connections to the panel.

Connection of the Front Panel

Instructions for re-hooking the front panel and reconnecting the electronic board.

Pre-use Checks

Checks to perform before powering up the electrical panel.

Compressor Motor Circuit Breaker Calibration

Step-by-step guide to correctly calibrate the motor circuit breaker for the compressor.

Closing the Electrical Panel

Steps to close the electrical panel after connections and calibrations are complete.

Parameter Programming

Control Panel

Overview and labeling of the AK-RC 113 control panel components.

Front Keypad

Description of the functions of each button on the front keypad.

LED Display

Explanation of the various LED indicators and their meanings on the display.

General

Explains the two programming levels (Level 1 and Level 2) for the controller.

Key to Symbols

Defines the symbols used for increasing/decreasing values and muting alarms.

Setting and Displaying the Set Points

Instructions on how to display and modify the SETPOINT temperature.

Level 1 Programming (User Level)

Steps to access and navigate the Level 1 programming menu.

List of Level 1 Variables (User Level)

Details of Level 1 programming variables with their meanings, values, and defaults.

Level 2 Programming (Installer Level)

Instructions on how to access and use the Level 2 installer programming menu.

List of Level 2 Variables (Installer Level)

Details of Level 2 programming variables for installers.

Switching on the AK-RC 113 Electronic Controller

Procedure for powering up the electronic controller after wiring.

Cold;Hot Activation;Deactivation Conditions

Conditions for activating and deactivating the compressor in cold and hot modes.

Manual Defrost Activation; Deactivation

How to activate or deactivate defrost manually using the dedicated key.

Defrost with Thermostated Resistances

Configuration for resistance defrost and its parameters.

Hot Gas Defrost

Note on hot gas defrost availability for this electrical panel.

Pump Down Function

Information on selecting the PUMP DOWN functioning mode for the compressor.

Password Function

How to activate and use the protection password function.

Modbus Connection

Net Configuration with Modbus-RTU Protocol

Scheme for RS-485 connections with Modbus-RTU protocol.

Diagnostics

Diagnostics by Means of Alarm Codes

Explanation of alarm codes displayed on the panel and their solutions.

Troubleshooting

Common causes of anomalies and operations to perform for troubleshooting.

Maintenance

General Safety Rules

Essential safety precautions before performing maintenance on the electrical system.

Maintenance

Scheduled maintenance tasks and frequencies for the electrical panel.

Appendices

AK-RC 113 Wiring Diagram

Wiring diagrams for OPTYMA™ Control (4 HP and 7.5 HP) three-phase panels.

Part List

A list of all components with reference numbers for the electrical panel.

Ordering

Danfoss OPTYMA Control Specifications

General

Protection Class	IP20
Type	Electronic controller
Number of Relays	2
Communication	Modbus RTU
Storage Temperature Range	-20°C to +70°C
Number of Digital Outputs	2