Two steps to improve the safety of your soft gas application

Thursday, 19 April, 2018

Hot gas defrost is a very common and efficient method defrosting used within industrial refrigeration, though it does pose a significant safety risk if the injection of hot gas into the evaporators is not carefully controlled. To minimize this risk, Danfoss has engineered a solution that safely controls your hot gas injection: The ICSH Dual Position Solenoid Valve.

Complying with the latest IIAR safety recommendations for soft gas applications, the ICSH Dual Position Solenoid Valve provides a gradual, time controlled opening for a smooth pressure build-up in the evaporator before it opens the flow to 100% for full defrost. This two-step approach prevents hydraulic shocks, thereby improving the overall safety of the refrigeration system. Unless the soft opening in step one has been activated, the default ICSH configuration ensures that the full opening in step two does not occur.

The ICSH Dual Position Solenoid Valve opens the flow thorough the main valve in two steps via two EVM-NC solenoid valve pilots. The time delay between the two steps can be controlled either by a PLC, a controller, or a timer. Once the EVM-NC for step one is energized, the main valve will open for approximately 20% of the main valve full capacity. After a pre-defined delay, the EVM-NC for step two will be energized and open fully equivalent to 100% of the main valve full capacity.

The ICSH Dual Position Solenoid Valve is based on the ICV platform and shares the same function module as the ICS and the ICV housing. The top cover is also compatible with ICF 50 and ICF 65.

The new ICSH valve is engineered with the following benefits to improve safety and optimize the overall performance of your refrigeration:

  • Improved operational safety, preventing hydraulic shocks in the hot gas line
  • Compliant with latest IIAR safety recommendations on soft gas applications
  • Easy to install and upgrade, as are all products in the Danfoss ICV platform
  • High design flexibility—ICSH top-covers are interchangeable with Danfoss ICS and ICF Large valves
  • Reduced risk of leakages thanks to fewer weldings compared to the number of weldings needed when installing individual valves or valves in parallel
  • Easy system design with the Coolselector®2 application tool
  • Compact design to save space

To explore how the ICSH Dual Position Solenoid Valve can improve your industrial refrigeration system, please visit