Dustin Hufsey,
Proudly Serving the Mohave County Area.
Proudly Serving the Mohave County Area.
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Dustin Hufsey,

Understanding Superheat And Subcooling In An HVAC System | Air Conditioner Repair | Kingman, AZ

Subcooling and superheat are two technical terms in the air conditioning industry that measure the refrigerant reading. Superheat temperature measures the refrigerant boiling point in a vapor form, while subcooling measures the coolant in liquid form and below evaporation levels. air conditioner repair technicians use a specialized mathematical chart to calculate the subcooling and superheat temperatures.

What is Superheat in an HVAC?

This refers to the temperature of refrigerant vapor measured above the boiling point. This reading shows the amount of coolant flowing through the evaporator coils and whether it is enough. If the temperature reading is too high, that could mean that the coolant isn’t sufficient. As a result, the HVAC system will need to be more efficient. In contrast, when the reading is too low, much of the refrigerant in the liquid state enters the evaporator and might cause compressor flooding. This particular issue needs the immediate attention of an air conditioner repair technician as it could damage the compressor.

How is Superheat Measured?

Defining the suction line pressure is the first step in determining the superheat temperature. The technician follows the chart with this measure to determine the corresponding saturation temperatures. The professional allows the HVAC system to run for 15-20 minutes for more accurate results. They will then measure the refrigerant temperatures using the temperature probe.

What is Subcooling

Subcooling is when the coolant is cooled at temperatures lower than the required minimum temperatures. Various reasons could make subcooling arise, including overcharging, faulty heat pressure control, underfeeding, restricted metering device, and overcharging. Have you noticed your system efficiency has reduced? Having an air conditioner repair pro check it up would be the best action. They might diagnose subcooling as the culprit.

Benefits of Measuring Subcooling and Superheat Temperatures

These critical measurements determine the HVAC system’s efficiency and performance. The air conditioner repair technician must check these measurements during the routine maintenance visit. Below are the benefits of regularly checking the superheat and subcooling temperatures:

Improved Efficiency

Subcooling and superheat readings are critical as they help improve the efficiency of your HVAC system. Insufficient or overcharged refrigerants normally cause inefficiency. Hence, regularly checking the two can help determine the right step that you should take. Has your HVAC become inefficient all of a sudden? Talk to an air conditioner repair technician about inspecting the refrigerant levels and quality. If undercharged because of a leak, they will refill the unit. If overcharged, the technician will empty some of the coolants to ensure that it is appropriately charged.

Fast and Easy Diagnosis

Repairing your heating and air conditioning system can take considerable time trying to diagnose the problem. At times, even the most experienced technicians cannot just tell the issue with your unit by looking at it. They have to check the subcooling and superheat temperatures to Accurately pinpoint the problem. Since compressor and evaporator issues have very similar characteristics, it could be confusing to know the exact problem without checking these measurements.

Avoid Overheating

This problem may damage your entire HVAC system, not only the compressor. Low refrigerant levels and a lack of lubrication usually cause it. Whenever the refrigerant levels are low, the HVAC compressor starts to overheat. Whenever this happens, you’ll first notice reduced efficiency. Overheating can prove detrimental as it may damage the other parts of the heating and cooling system, resulting in expensive air conditioner repairs.

Causes of Low Subcooling and High Superheat

Liquid Line Restriction

The coolant passes through the liquid line of an HVAC system. A normal flow means that the HVAC system can maintain the optimal levels of the refrigerant. However, a blockage or restriction that inhibits the flow means that problems will be inevitable.

Malfunctioning Metering System

Your HVAC system’s metering unit is supposed to control the volume of refrigerant flowing through the refrigerant lines. If proper control doesn’t happen for whatever problem, you might experience low or high refrigerant levels. Unfortunately, this results in low subcooling or a high superheat. Hence, ensure that the air conditioner repair company also checks the metering system when they come for a maintenance visit.

Excess Air in Evaporator Coils

The volume of air flowing in the evaporator coils must be regulated to keep the coolant levels optimum. Unfortunately, there is excessive air in these coils sometimes, making the coolant evaporate from the HVAC.

Limited Airflow Inside the Evaporator

A limited airflow in your unit’s evaporator coils could be better too. Since neither more nor less airflow in the evaporator coils is better, the air levels must be regulated to ensure that only the right volume passes. This will ensure that the coolant remains at the right levels.

Role of Refrigerant in the HVAC System

The coolant is an important part of your heating and air conditioning system. Hence, you must ensure that your HVAC system has the right levels. The refrigerant is a cooling agent that aids in heat transfer and facilitates your home’s cooling. Unless you are a trained air conditioner repair technician, it is advised that you not recharge the HVAC system under any circumstance. The refrigerant;

Protects the System from Overheating

Besides aiding in the heat transfer process, the refrigerant prevents the HVAC system from overheating. If the unit doesn’t have the right coolant levels, it will undoubtedly overheat, resulting in damage. Therefore, ensure that the air conditioner repair technician checks the refrigerant levels when they come for routine maintenance.

Ensures a Better Efficiency and Performance

For the HVAC system to perform efficiently, there must be sufficient refrigerant. This prevents the unit from overworking, ensuring you get the desired level of efficiency. Right refrigerant levels mean that your system will attain optimal efficiency.

Do you need to know either of the refrigerant measurements above? Contact us at Pitzer’s One Hour Air Conditioning & Heating of Mohave County today.

See our previous blog on this topic here.

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