In a refrigeration circuit, the evaporator coil plays a critical role. Part of its responsibility is creating the controlled pressure drop necessary for the refrigerant to change phase, the bulk of which occurs via the system’s metering device, such as a thermostatic expansion valve (TXV).

We serve a diverse customer base at Super Radiator, one segment of which are what’s known as original equipment manufacturers (OEMs). Though we classify them together, OEMs and their respective industries all operate differently. Some customers are recurring business – they need coils every week consistently over a given timeframe – we’ve seen this with commercial HVAC or datacenter OEMs. Other customers need us to supply coils for projects that may arise infrequently over a period of years, which describes industries like transit cooling.

Oftentimes, using stainless steel components seems like a simple solution to corrosion on coils. You may see fins or tubes or other parts of the system show signs of corrosion, and it seems that the best option is to change the coil to stainless steel, solving the corrosion problem permanently. While this seems like a simple solution to a significant problem in the HVAC, industrial, and commercial systems where coils are found, the answer to the question “should I make an all-stainless coil?” is far more complex.

In plate fin heat exchangers, the fins themselves play a critical role. They provide the extended surface area needed to achieve effective heat transfer between a gas on the finside and a fluid on the tubeside.

This article has been updated. It is accurate as of 9/23/20.

For commercial operations that rely on effective heat transfer, external corrosion of heat exchanger components is a major concern. When left unchecked, corrosion can significantly reduce a coil's effectiveness, but sometimes it’s difficult to know which anti-corrosion option best meets your needs.