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AC Repair Signs Of A Failing Thermostatic Expansion Valve | The Colony, TX

AC Repair Signs Of A Failing Thermostatic Expansion Valve | The Colony, TX

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Every single component of an air conditioning system is vital for efficient operation at peak performance. The thermostatic expansion valve (TXV) controls the amount of the coolant liquid due to the temperature and pressure in the evaporator, affecting the functioning of the air conditioning system.

Like other parts of the unit, TEV can also have issues due to the superheating levels that cannot change the boiling refrigerant into a gaseous form for cooling the house. If your air conditioner fails to cool your home in The Colony, TX, you should get urgent AC repair services to evaluate the unit and find where the problem could be.

What Is a Thermostatic Expansion Valve?

It is a metering device also known as a constant superheat valve that makes pressure drop and transforms at the liquid line in the evaporator coils at the valve. At this point, the refrigerant will boil, changing from its liquid state to a gaseous state, facilitating the cooling process of the air conditioning system. The boiling coolant absorbs heat from your house or space.

How the Thermostatic Expansion Valve Works

The metering tool uses an external equalizer to measure the temperature and pressure at the end of the evaporator coil. The bulb in the TXV measures the temperature, which starts an opening force. The external equalizer measures pressure, providing a closing pressure in the evaporator coils that creates a balance that maintains the evaporator superheat at the optimal levels in the evaporator. When the superheat is efficient in the evaporator, it controls the flow of excessive liquid refrigerant from flowing to the compressing unit. If the coolant is excess in the evaporator coils, it might get to the compressor, causing possible compressor failure that might require costly repair services.

What Causes the TEV to Fail?

The underfeeding and overfeeding of the evaporator coils affect the efficiency of the AC to perform its intended cooling duty. The reason behind the malfunctioning thermostatic expansion valve include:

  1. Contaminants
  2. Moisture
  3. Rub out on the bulb tube
  4. Bulb insulation
  5. Poor installation

The failed valve causes a difference in the opening and closing forces in the evaporator that creates an imbalance of the superheat, making the refrigerant stop boiling, thus failing to absorb heat from your rooms. It increases temperature-related discomfort compelling you to call for urgent AC repair services. The imbalance can be overfeeding or underfeeding due to the far open feeding and too far closed. Underfed evaporator coils mean that the boiling coolant is feeding far through the evaporator coils, causing a low superheat that cannot boil the refrigerant. The overfeeding evaporator coils imply that the boiling refrigerants in the evaporator coils are insufficient, making the superheat high. The unequal distribution of the boiling coolant in the evaporator might seem like a minor issue, but it is not. It is a problem that requires immediate repair services from an expert in The Colony, TX, to find the root cause of the issue and fix it.

Signs of a Failing TEV

Having a functional AC throughout the hot season is essential because it provides comfort and prevents heat strokes. Several signs and symptoms help AC repair service providers and homeowners to know there is a problem with the thermostatic expansion valve in your HVAC system. Here are some of the indicators that your TEV is malfunctioning.

Poor Performance of the Cooling System

Top on my list of signs is the cooling performance of the air conditioning unit. The thermostatic expansion valve helps the evaporator coils and the refrigerant to produce cold air to your house for increased comfort. However, when the refrigerant levels getting to the evaporator are low, it becomes a hassle for the pressure and temperature in the coils to control the superheat that makes the boiling coolant evaporate and suck the warm air out of your space. The repair service contractor will recognize the issue is with the evaporator the moment warm air flows out of the air conditioner instead of cold air.

Compressor System Constantly Running

Another symptom of a failing thermostatic expansion valve is the constant running of the compressor. An AC repair service technician can identify the problem as a malfunctioning expansion valve that forces the compressor to continue pumping the refrigerant into the air conditioning unit without stopping after achieving the required cold temperatures. The problem occurs because the valve cannot control or stabilize the correct amount of refrigerant flow to the AC system, causing the compressor to overwork and suddenly fail. A malfunctioning compressor is a big issue because the AC repair service technician can recommend a replacement.

High Energy Bills

When the air conditioning equipment in your home struggles to produce cool air to your home, it consumes a lot of energy that increases your utility bills. A failing expansion valve cannot regulate the refrigerant flowing into the compressor and condenser, causing over and underfeeding of the evaporators.

The malfunctioning TXV will affect how to superheat boils the refrigerant to a gaseous state, failing to get the warm air out of the rooms. Having a qualified AC repair service contractor to fix the issue as soon as possible will save you some money off your utility bills.

Ice On The Evaporator Coils

The work of the thermostatic expansion valve is to depressurize the refrigerant to help it cool your home. When the valve is not functioning, the depressurizing will stop.

The minute TEV malfunctions, the liquid refrigerant will freeze into a solid-state rather than heat up to a gaseous state. It will freeze everything in the evaporator, causing frozen coils, ice on the vents, and the suction line. It is a problem that requires urgent AC repair services to fix the faulty expansion valves.

Noise Coming Out of The AC

A broken or damaged thermostatic expansion valve causes the AC to produce unusual squealing, clanging, or banging noises that continue to worsen with time. The moment you notice these sounds when you turn on your AC should compel you to call for immediate AC repair services.

Call Us!

If you want the best HVAC company for AC repair services, contact One Hour Air Conditioning & Heating of Dallas. We serve clients living in The Colony, TX, and the surrounding areas. Our company has qualified and skilled technicians that address a wide range of heating and cooling issues, including installations, repairs, and replacements.