How can you tell when a filter drier is stopped up?

How can you tell when a filter drier is stopped up?

• A. It will have a pressure drop of more than 2 psi across the filter
• B. It will vibrate
• C. It will feel warm
• D. It will show a higher-than-normal suction temperature

Answer: (A)

When a filter-drier becomes stopped up, the flow path through it narrows, causing more resistance for the refrigerant. That added resistance shows up as a larger pressure difference between the drier’s inlet and outlet. In practice, a differential of about 2 psi or more is used as a quick, reliable sign that the drier is clogged. This direct measurement across the component is the most effective way to assess its condition. Vibration isn’t a dependable indicator of a blocked drier; it points to other mechanical issues and isn’t caused by the drier’s restriction. Feeling warmth on the drier isn’t a reliable sign either, since temperatures can vary for many reasons in the system. A higher-than-normal suction temperature can result from various faults in the refrigeration cycle and doesn’t specifically prove the filter-drier is blocked.

When a filter-drier becomes stopped up, the flow path through it narrows, causing more resistance for the refrigerant. That added resistance shows up as a larger pressure difference between the drier’s inlet and outlet. In practice, a differential of about 2 psi or more is used as a quick, reliable sign that the drier is clogged. This direct measurement across the component is the most effective way to assess its condition.

Vibration isn’t a dependable indicator of a blocked drier; it points to other mechanical issues and isn’t caused by the drier’s restriction. Feeling warmth on the drier isn’t a reliable sign either, since temperatures can vary for many reasons in the system. A higher-than-normal suction temperature can result from various faults in the refrigeration cycle and doesn’t specifically prove the filter-drier is blocked.