You may have never heard of static pressure and still wonder what it is, or you may have figured out that it’s necessarily a good thing. Either way, this article will enlighten you and help ensure your HVAC system remains free from interference.
What even is static pressure? Static pressure is the resistance to airflow in ductwork. Cooling and heating systems supply air through ducts to rooms to circulate warm or cool air. However, some factors inhibit airflow. It is impossible to have no resistance at all, but the idea is to keep it in check.
For example, if a large amount of air is being forced into a small opening, there will be a lot of resistance. This is similar to placing your hand over the nozzle of an air hose. The more you try to shoot the stream out, the harder it becomes; eventually, you can’t push any more air out. High static pressure means a lot of resistance; low static pressure means little resistance. The ideal static pressure would be close to zero.
Why does static pressure matter? Static pressure can wreak havoc on your HVAC system because it can cause fans and blowers to work harder than they need to. It also increases the likelihood of coil freezing and compressor failure due to excessive workloads. If you notice increased noise coming from the system, it may be a sign that there is high static pressure that needs correcting.
Signs of High Static Pressure
Increased or persistent noise in the system. It may just be a little louder than normal, but it can become quite loud when airflow is restricted and worsens as the system heats up. The noise can come from anywhere in the system.
Decreased indoor air quality. Warm air carries contaminants more easily. If the air passes through a restricted path, it will carry more contaminants to the next room.
Inconsistent or spotty airflow. If there is high static pressure, the heat may only be blowing in one area of the room, or the air may only come out at one end of an outlet. This can create hot and cold spots and makes it hard to feel comfortable no matter where you sit in a room.
Higher energy bills. The higher the static pressure, the bigger the workload for the fans and blowers in your system. That means more work and more energy. Not only that, but a system with high static pressure will work harder and shorten its lifespan. This leads to the energy bills skyrocketing.
What Causes High Static Pressure?
There are three main culprits that cause high static pressure.
- The air returns are undersized
- The indoor coil is dirty
- The air filter is clogged or too restrictive
The Air Returns Are Undersized
The air returns in the room should be sized to match the air output of your system, usually measured in cubic feet per minute. If an undersized return is connected to an oversized output, high static pressure will occur. This is a common problem and one that can quickly be resolved by installing a return that matches your system.
The Indoor Coil Is Dirty
As air passes through the coil, it is heated or cooled. The coil is also where a lot of dust accumulates. If your air filter isn’t up to snuff, you can experience static pressure buildup because the dirty coil has difficulty moving the air. This situation worsens if the coil is dirty or restricted on top of already having a higher output than the return can accommodate.
The Air Filter Is Clogged or Too Restrictive
If the filter is clogged, it slows down airflow. When the airflow is slowed, static pressure rises. Too restrictive refers to filters that are too small for the system. It is important to use the proper size filter to prevent this from becoming an issue.
What happens to your system? High static pressure causes a decreased lifespan of the system. Higher workloads can result in a shorter life span of your units. For example, when fans and blowers work harder to move air through a restricted path, they may overheat and burn out. Or the compressor may be under too much pressure and wear down quicker. Unique Heating & Air Conditioning Inc. in Northglenn, CO, we install and maintain heating and cooling systems.
In conclusion, you must always be wary of static pressure in your system. High static pressure can cause a lot of physical and monetary damage. This is why it is important to keep the return vent properly sized and clean the coil and filter regularly. We offer heating, cooling, and indoor air quality services. Contact Unique Heating & Air Conditioning Inc. today for all your heating and air conditioning needs.