Why did I hear a hissing sound when hooking up my refrigerant lines?

When connecting the lines, the high-pressure refrigerant gas is escaping from the connection point, usually due to a slight pressure difference between the lines being joined, creating a small release of gas that sounds like a hiss; this is a normal occurrence, as well as not hearing the hissing sound, that is also perfectly normal.

However, if the hissing sound is continuous, it could indicate a potential issue. In this case, we recommend performing a basic leak test on the lines as soon as possible to ensure there are no larger problems. If a leak is detected, please record a video of the leak and send it to MRCOOL for further assistance. Additionally, if a leak is found, shut off the system’s valves and disconnect the line to prevent any further issues.