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10 Common Causes of HVAC Airflow Problems

10 Common Causes of HVAC Airflow Problems

More often than not, cooling or heating problems at home or in the office are caused by airflow issues. It may not seem a bad thing at first, but incorrect and insufficient airflow can cause problems in the long run and even circulate diseases. Here’s what you should know about HVAC airflow problems and what you can do about them.

If you notice that your HVAC system is no longer functioning as effectively as before, you may need an HVAC specialist to inspect, diagnose, and fix the problem.

Signs of HVAC Airflow Problems

 Know what red flags to look out for

Watch out for these tell-tale signs of common HVAC airflow issues:

  • Presence of Hot and Cold Spot

Varying temperatures inside a single room is the first sign you may be having issues with the airflow of your HVAC unit. If some spaces, especially near equipment, feel warm but others are excessively cold, it warrants the attention of a specialist.

  • Pressure Imbalance

Pressure imbalance is caused when large amounts of air are being forced in or sucked out of a room, causing a significant pressure difference between the outside and inside. If you find doors slamming by themselves or hear whistling sounds in a drafty area, this may be caused by poor airflow.

  • Weak or No Airflow from the Vents

Weak or no airflow is an obvious sign that something Is wrong with your HVAC vent.

  • Air Conditioning System Blows Warm Air

An AC unit blowing warm air is not normal and should be inspected.

Common Causes of HVAC Airflow Problems and Solutions

Ignoring the problem for some time can strain and, ultimately, cause a system failure. Fortunately, identifying the causes behind these issues is easy and repairs are relatively inexpensive.

Below are the 10 most common causes of airflow problems and how to address them:

1. Condenser Unit Obstructions

Condenser units must be free from any obstructions

Air conditioning systems usually have a condensing unit, located outside or in a mechanical room. These units, especially those placed outside, can easily become obstructed with leaves or debris that have piled up around them. Even those inside mechanical rooms can also be obstructed by other equipment or items.

This problem is an easy fix. Simply, remove any obstructions and clear the area surrounding your condenser unit.

2. Blocked Vents

If you notice the system isn’t cooling your space properly, you should check your vents. A piece of furniture or fixture could have been moved in front of it, compromising the airflow. Simply move the obstruction away and possibly rearrange the furniture and fixtures inside your room to avoid any future possibility of them blocking the vents.

3. Clogged Filters

Dust accumulation can keep air from flowing properly

Filters have one important job — to trap dust and debris in the air and keep them out of your system and ducts. If the dust build-up becomes too much, it may start to impede the flow of air, producing hot and cold spots and stale air. Keep in mind that overloaded and clogged filters can also damage other aspects of the HVAC system, not just its airflow.

When was the last time you cleaned your air conditioner’s filter? Check and change the filter according to the manufacturer’s instructions, which is typically as often as once a month.

4. Ductwork Problems

Some airflow problems could be traced to problems in the ducts. For one, if dust gets past the clogged filters, it will begin to accumulate in the ductwork. Ducts are already too narrow, so any build-up can easily compromise the capacity of your air conditioner. It is also not unheard of for rodents, birds, or insects to nest in HVAC ducts.

The ductwork can also develop holes and cracks where air can seep through. When this happens, airflow for heating and air conditioning is reduced and unlikely to reach the rooms.

To deal with ductwork problems, schedule an inspection with someone who has knowledge and experience on how to increase airflow in the ductwork.

5. Thermostat Issues

Malfunctioning thermostat prevents the HVAC system to register changes

Airflow problems don’t necessarily mean there’s something wraith with the HVAC system itself. The problem may lie in a malfunctioning thermostat.

A thermostat that’s not functioning well may not be able to register any temperature adjustments you make. Another possibility is that the thermostat simply needs a change of batteries.

Change the batteries first to see if this is the case. If this doesn’t work, check the thermostat troubleshooting guide. Consult a professional if neither solutions resolve the issue.

6. Insufficient Refrigerant Levels

Low refrigerant levels are one common problem among HVAC systems, especially if it’s an old one. A leaking refrigerant gradually lowers the system’s performance, reducing its cooling ability and causing airflow issues.

Remember that exposure to the refrigerant can be dangerous. Inspecting and repairing a suspected leak must only be conducted by an expert.

7. Sluggish Fan

The HVAC system contains blower fans that move the air through the ducts and into your space. Fans specifically used for kitchen ventilation can be coated with grime and grease, hampering its performance. If the blower motor slows down, it can disrupt the HVAC airflow.

Fortunately, this issue can easily be resolved by simply cleaning the fan regularly.

8. Dirty Condenser Coils

The condenser coil is responsible for releasing heat from the refrigerant. Since it is often exposed to the elements, the coils tend to accumulate so much dirt that they can no longer function. Your unit then has to work on overdrive, resulting in your unit overheating and experiencing airflow issues.

Condenser coils need to be cleaned once or twice a year.

9. Incompatible HVAC Capacity

The size of your HVAC unit must depend on the size of your space

When installing an HVAC system, it must be relative to the size of the area the unit must cool. A small HVAC unit won’t effectively cool a large space. Consequently, bigger is not always better when it comes to HVAC sizing. An HVAC system that is way too large for the space will cycle on and off frequently, impeding airflow. The HVAC system can not run long enough to remove humidity in some areas, making it feel dense and uncomfortable.

If you feel as if your unit has been running inefficiently, you better have an HVAC expert assess your unit.

10. Outdated HVAC Design

If you’ve renovated the room, you also need to consider switching your HVAC system to match the new layout and size. problems with airflow after a renovation might be caused by the system’s inability to supply sufficient heating or cooling. You might need to check your old HVAC airflow diagram and make the necessary changes to either the layout or the system.

Remember to consult an HVAC design expert to correctly assess and plan the needed changes in your ductwork.

HVAC airflow problems may have a variety of possible causes, but all of them can easily be mitigated with proper and regular HVAC maintenance.

If you need airflow troubleshooting, call HVAC Link at (416) 567-3498. With over 10 years of experience in serving the Greater Toronto Area, you can count on us to deliver innovative solutions.

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