Detecting Obstructed Capillary and Refrigerant Gas Shortage in Refrigeration and Air Conditioning

We will explore how to identify whether a malfunction in an air conditioner or refrigerator is due to a lack of refrigerant or an obstructed capillary tube.

Two common issues frequently encountered in refrigeration equipment are the shortage of refrigerant and capillary obstructions. Distinguishing between these problems can be challenging as their symptoms often overlap. In this article, we will outline the distinct symptoms of each issue.

Identifying a Lack of Refrigerant

  1. Low Refrigerant Pressure: A common indicator of refrigerant shortage in refrigeration equipment is lower-than-normal refrigerant pressure on both the high and low sides. This can be measured with a manometer while the equipment is running. The extent of pressure drop depends on the degree of leakage.
  2. Reduced Compressor Amperage: Another telltale sign of insufficient refrigerant is a lower-than-average amperage draw by the compressor. This is due to the reduced energy required for compressing less gas as a result of the decreased refrigerant volume.
  3. Capillary Tube Inspection: To confirm the presence of a refrigerant shortage, check the capillary tube while the equipment is operational. A dry and warm capillary tube is a strong indication of a healthy capillary and further confirmation of the lack of refrigerant.

Identifying an Obstructed Capillary

  1. Refrigerant Accumulation: When a capillary tube becomes obstructed, the refrigerant accumulates in the condenser. Over time, the pressure on the low side drops as there is no refrigerant left to compress; instead, it accumulates in the condenser. The high side pressure in the condenser decreases as the gas condenses into a liquid.
  2. Reduced Compressor Suction: The absence of gas in the compressor’s suction leads to reduced amperage consumption by the equipment. In such cases, you might observe a gradual decrease in the refrigerant pressure at the evaporator and slightly lower amperage compared to the normal range.
  3. Capillary Condition: Remember that a dry and warm capillary tube indicates it is not obstructed. In contrast, if the capillary tube is wet or cold, particularly towards the tube’s end, it signals an obstruction.
  4. Multiple Capillaries: Some air conditioning systems incorporate multiple capillary tubes. If one capillary is obstructed, you’ll notice it’s wet or cold, while the others will maintain a normal temperature. This discrepancy clearly points to an obstruction in the problematic capillary.

By understanding these distinctive symptoms, you can accurately diagnose whether the issue lies in a lack of refrigerant or an obstructed capillary tube in your refrigeration and air conditioning equipment. Proper identification will guide you in performing the necessary maintenance or repairs to keep your equipment functioning efficiently.

Leave a Reply

Your email address will not be published. Required fields are marked *

Exit mobile version