Homeowners are on the constant lookout for ways to reduce their energy costs. When it comes to their air conditioner, they know that a more energy efficient AC unit translates into lower home cooling costs. One of the best ways to make your AC more energy efficient is to contact PFO Heating & Air Conditioning.
Our HVAC services can help your air conditioner run at peak performance, using less energy. We offer AC tune-ups, maintenance, and air conditioner repairs. Also, we can recommend other effective strategies that can help reduce your summer energy bills. Call today to schedule an appointment.
One of the most frequent questions that we get is whether or not it is a good idea to close vents to unused rooms. In this article, we will answer this question and provide some energy tips that you can use during the summer.
Can Closing HVAC Vents In Unused Rooms Save Money?
Closing HVAC vents will not cause your heating or cooling system to work less. Consequently, closed vents do not cut your cooling costs. Instead, it will increase the pressure in your air ducts. This pressure causes your air conditioning system to develop problems which lead to significant repair costs. These problems generally vary depending on the type of blower motor that your air conditioner has. Some of the issues include
- increased energy use
- increased duct leakage
- frozen air conditioner coil
- dead compressor
- lower airflow in ducts
Below is some more information to help you answer the question, “Can closing HVAC vents in unused rooms save money?”
Types of Blower Motors
Your HVAC system relies on its blower motor to distribute the conditioned air throughout your home. In particular, the blower pulls warm air from your home through the return ducts. It also pushes the conditioned air back into your home through the supply ducts. There are two main types of blower motors: electronically commutated motor (ECM) blowers and permanent split capacitor (PSC) blowers.
The main difference between these two blower motors is an ECM blower motor can vary its speed according to the workload. However, a PSC motor always blows conditioned air at a fixed rate. For this reason, you will find the former in high-efficiency HVAC systems. You will see the latter (PSC motor) in lower-efficiency systems.
How Closing HVAC Vents Affects Blower Motor Performance
Both ECM and PSC blower motors work by pushing air against some maximum pressure difference. Typically, this pressure difference is 0.5 inches of water column (iwc). However, specific factors may cause the maximum pressure difference to increase significantly. These factors include dirty air filters and narrow supply ducts. Another factor that raises this pressure is closing HVAC vents in unused rooms. When this happens, an ECM blower motor will work harder to overcome the extra pressure inside your ductwork. When this happens, it will use more energy, causing your cooling costs to rise.
On the other hand, a PSC blower motor always blows at a fixed speed. It cannot ramp up to overcome the extra pressure in your ducts. When it needs to overcome the extra load, a PSC blower motor will slow down. This aspect means you will get less conditioned air from the open AC vents. Your home will not feel as comfortable. Even worse, less airflow in your air conditioning system could potentially cause the evaporator coils to freeze over. This process eventually causes severe damage to the compressor, which is an expensive component to replace.
Increased Duct Leakage
Energy Star says that the average home in the US loses anywhere from 20% to 30% of conditioned air due to duct leaks. This claim means that your home is already losing conditioned air and the extra pressure in your ductwork will make this problem worse. Your HVAC system will have to work harder and consume more energy to cool your home up to your requirements, translating to higher cooling costs.
Energy Tips You Can Use During The Summer
Is Your Air Conditioner Energy Efficient?
You cannot save money by closing HVAC vents in unused rooms. Doing so will not change what your HVAC system’s blower motor is supposed to do. In fact, closing HVAC vents will cause pressure to build up in your ductwork because blower motors are designed to work at a maximum pressure difference. Depending on the type of blower you have in your HVAC, this can cause problems such as lower airflow, frozen air conditioner coil, indoor comfort problems, a cracked heat exchanger in furnaces, and a dead compressor. Therefore, it is best to use alternative methods to reduce the energy use in your home.
When you need to improve your home’s energy efficiency, reach out to the professionals at PFO Heating & Air Conditioning. We can service your air conditioner so that it runs at peak efficiency, reducing your energy bills during the summer. Likewise, we can service your heating system to help make your home more comfortable and energy efficient during the winter. Our heating and cooling technicians have the training and experience to understand how to best meet your needs. Be sure to give us a call to schedule an appointment.