Final answer:
A suction filter drier should be replaced when the pressure drop across it exceeds a certain value, typically around 2-3 PSI. This indicates that the filter is becoming clogged and no longer effectively removing contaminants from the system.
Step-by-step explanation:
A suction filter drier should be replaced when the pressure drop across it exceeds a certain value. The specific value will vary depending on the manufacturer's recommendations, but a common threshold is around 2-3 pounds per square inch (PSI).
When the pressure drop across the filter drier exceeds this threshold, it indicates that the filter is becoming clogged with debris and is no longer effectively removing contaminants from the system. This can lead to reduced system performance and potential damage to the equipment.
Regular maintenance and monitoring of the pressure drop across the suction filter drier is important to ensure optimal system operation and longevity.