Many people think that if they block one or more of the cold air returns around the home, they can make the others work even better. Unfortunately, the opposite is true.
When you block any cold air return throughout your HVAC system, the whole thing has to work harder – and the results you get are nowhere near as efficient.
These little vents provide a return air supply to your air handler or blower compartment. They need to be unblocked to ensure air flows freely through the system.
The consequences of covered cold air returns are all negative:
1. Fan Speed Isn’t Affected
While many people suspect they can save money by arranging their cold air returns just so, that doesn’t turn out to be the case in practice. Fan speed doesn’t actually go down when fewer returns are active, so your electricity usage stays the same or actually goes up.
2. It Adds Positive Air Pressure
HVAC systems are carefully designed to support ease of air flow through a structure. Without returns, positive air pressure is created that fights against the optimal flow. That means air will get sucked up from cracks and gaps in the structure – especially around doors and windows.
3. It Leads to Costly Repairs
Since improper airflow adds so much stress to your system, it can lead to situations where very costly parts have to be replaced. For example, the coil can freeze over because temperature of the refrigerant isn’t properly regulated. This can ruin the outdoor compressor.
4. It’s Potentially Dangerous
Some problems caused by closing off air returns are dangerous. Most commonly, the heat exchanger might crack. Not only does this require replacement of the system, but it releases carbon monoxide gas into the air. That may make an entire property unsafe.
Long story short: It’s never a good idea to cover up cold air returns. Don’t succumb to the temptation, and always check that air is circulating freely when you move furniture.
If your HVAC system isn’t performing the way you would like, it might have other efficiency issues. To find out more, contact us today.