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Couple Sweating Below An AC Unit That Is Not Working Properly

17 Jul 2023

Author: Jeff O'Hara

As we head into the stifling, hot summer months in Houston, this is the worst time to discover a problem with your air conditioning system

To resolve weak airflow issues, it is recommended to:

  • check and replace air filters regularly
  • clear any obstructions near vents or registers
  • inspect and maintain the blower motor
  • ensure proper ductwork installation and integrity
  • have the HVAC system professionally sized
  • clean the outdoor condenser unit
  • inspect and repair fan motor issues
  • verify that dampers are open where needed. 

Consulting with a professional HVAC technician from Nick’s Air Conditioning can help identify and address the specific cause of weak airflow in your AC system. 

What Causes Weak Airflow from My HVAC System?

Clogged Air Filters

A dirty or clogged air filter restricts airflow into the system, which will cause air to flow weakly from the vents. Air filters are the most commonly neglected item in the home that requires regular maintenance, and dirty filters are the root of many HVAC issues. Check your air filter to see if it looks clean, and if you haven’t changed it in the last six months, pop a new one into your AC system. 

If you’re not sure where your HVAC air filter is or aren’t sure about how to install a new one, call Nick’s Air Conditioning and schedule an HVAC tune-up. Your HVAC technician will happily show you where your air filter goes and how to install it yourself. 

Blocked or Closed Vents

Ensure that all supply and return vents are open and aren’t blocked by curtains, furniture, throw rugs, or anything that could impede airflow. Closed or blocked vents can reduce airflow to a room, leaving it feeling too warm and humid. 

Closed vents are easy enough of a problem to solve, but if your vents still aren’t putting out any significant airflow after being opened, the problem could be collapsed or crushed ductwork. 

Ductwork Issues

Problems with the ductwork, such as leaks, improper insulation, or blockages, can create weak airflow issues. Have a licensed HVAC technician inspect the visible ductwork sections for any obvious tears or separations between ducts, which can draw warm attic air into the vents throughout the house. Aluminum and steel sections of your ductwork will probably last a lifetime without any issues; the main concern with ductwork is the “flexible” type of ducting that is standard in all HVAC installs. 

Flex duct can best be described as a giant “Slinky” toy with a thin plastic coating stretched outside the coil. The flex duct is then wrapped with a protective insulation layer before installation. Unfortunately, the flex duct is very susceptible to developing cracks in the plastic sheathing due to extreme temperatures and exposure to high humidity. Flex ducts can also be easily crushed by inadvertently setting boxes on top of attic ducting or someone carelessly stepping in the wrong spot.  

In Houston, the average life expectancy of air conditioning ductwork is about 15 years, so we often recommend replacing any accessible flex duct when installing a new HVAC system. 

Blower Fan Problems

The blower fan moves air through the ductwork system and out of the vents. Voltage issues can cause the fan to run slower, causing less air to circulate throughout the house, leaving it warm and humid. Fan blades can get damaged or bent, leading to diminished airflow. 

The blower fan is a shared component between the heating and air conditioning systems and, as a result, is one of the few HVAC parts that see year-round use. Normal wear and tear in a blower fan assembly will appear as worn-out bearings, dry and brittle internal electrical connections, and weakened components. 

Lack of regular maintenance that includes, at a minimum, inspection, and lubrication of the blower fan unit can lead to premature failure. Regular HVAC maintenance should consist of cleaning any accumulated dirt or other debris from the motor, which could lead to overheating. 

Obstructed Condenser Unit

Your outdoor portion of your home’s HVAC system contains several key components critical to proper system operations. The compressor, the capacitor, and the condenser coil all share the space in that square metal box connected to your house via electrical cables and refrigerant lines.  

Being installed outdoors exposes the condenser unit to temperature and humidity extremes, direct sunlight, rain, wind, dirt, and debris. Simply put, your outdoor HVAC unit takes quite a beating all year round. As dirt and other debris get blown into the outdoor housing, it sticks to the humid condenser coil and often settles inside the fan assembly at the unit’s base.

Having the outdoor condenser unit cleaned on a regular basis is important not only to maintaining comfortable airflow throughout your home today but to ensure your system continues to serve your family for years. 

Let Nick’s Find Out Why Your AC Is Blowing Weak.

If your air conditioning seems like it’s “underperforming” this summer, call Nick’s Air Conditioning and schedule an HVAC check-up. As you can tell from the above blog, there are a multitude of reasons why your air conditioning isn’t performing up to expectations. 

Nick’s licensed and experienced HVAC technicians can narrow down the cause of your particular air conditioner woes, determine what needs to be done to correct them, and how to get your family cool and comfortable again. 

Relax, We’re on the Way!

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