What is superheat and subcooling?
Both terms refer to specific ways to check how much refrigerant your air conditioner or heat pump has. Measuring pressure is the most commonly used method of checking your refrigerant levels. However, pressure alone can be very inaccurate. Certain conditions like low airflow can cause refrigerant pressure to drop even though there’s plenty of it. Checking superheat or subcooling is absolutely the most accurate way to check refrigerant levels. Unfortunately it’s not often done. While I don’t believe it’s absolutely necessary under all conditions, I believe it is a necessity any time major repairs are performed and under other circumstances.
