How to Tell if Your HVAC System Uses too Much Energy
- It’s over 10 years old. Newer technology is up to 18 percent more efficient, right out of the box. Just look for the sticker with the manufacture date on the side of your unit.
- You experience humidity or excessive dust in your home. Duct leaks, controls, filtration and pressure problems are all at play here.
- Some rooms are too cold or too hot. Duct design, duct leakage and building leakage can all be culprits here.
- Your heating and cooling system is the wrong size. Does your furnace turn on, heat up and then turn off quickly? It’s probably oversized, a common “safe” move by HVAC contractors.
- You need to make constant repairs to the system. Bad duct design can restrict air, burning out heat exchangers, fans and controls.
- Your energy bills get more expensive while HVAC performance remains the same. Again, this is an indicator of systematic problems.
- Your HVAC unit isn’t ENERGY STAR rated. Modern fans, called “ECM,” can use dramatically less power to move air throughout your duct system.
Beyond just comfort and operating costs, it’s important to pay attention to the greater impact our HVAC systems have on the environment. The EPA states that the energy used by the average home accounts for twice as many greenhouse gas emissions as the average car. You wouldn’t drive around with smoke belching from your car, but your HVAC system might be in a similar condition. Existing HVAC systems generally run on gas, oil, electricity or wood. Electricity (sourced from coal) and oil produce large amounts of nitrogen oxide and sulfur dioxide. Older air conditioning systems use chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs), which, if released, may contribute to climate change and ozone depletion. Plus, an inefficient system can impact indoor air quality as you risk increasing levels of carbon dioxide, volatile organic compounds (VOC) emissions, mold and other contaminants.
How to Make Your HVAC System More Energy Efficient
If you have a heating and cooling system that’s less than a decade old, have a Home Performance/HVAC expert perform an annual tune-up. This person will: make sure the system’s controls work well and are safe; tighten the electrical connections; check the system’s settings; and lubricate the moving parts. He or she will also clean the different coils within the unit, check the refrigerant levels and replace broken parts. This professional servicing helps catch problems before they cause trouble and keeps your system in optimal working condition. Home Performance technicians can also assess larger issues, such as duct design and leakage; building shell leakage and insulation; and pressure dynamics in the house – all of which can affect proper performance.
Regular air filter replacement can also help improve your system’s performance. Depending on your system, you’ll need to change the air filter every one to three months. Dirty filters waste energy because they make an HVAC system work harder.
Duct maintenance. When you have your HVAC unit tuned up, it’s also a good time to make sure your home’s cooling and heating ducts are sealed and insulated well. A leaky duct can compromise an HVAC unit’s efficiency by up to 20 percent. Restrictive duct systems can shorten the life of the fan, controls and heat exchanger.
Programmable thermostat. Your home doesn’t need to maintain the same temperature all the time. Install a programmable thermostat so your HVAC system uses less energy while you’re at work, sleeping or on vacation. This simple measure can easily save 20 percent on energy.
Alternative energy sources. If your home is a good candidate, using solar or wind energy to power your home can help your electric-based HVAC system (like heat pumps) to become less dependent on fossils fuels.
If your heating and cooling system is 10 years old or you’re spending a significant amount of money on repairs, it’s time to replace it. Look for a system that has a high AFUE for furnaces/boilers (90 percent or better), a high HSPF for heat pumps (8.5 or better) and a high EER for air conditioners (12.5 or better). Before installing a new unit, make sure it’s the right size for your home by working with a qualified HVAC/Home Performance technician. An HVAC system that’s too large will short-cycle, reducing comfort and service life.
The best way to learn more about your HVAC system is to have an energy expert perform a Home Performance Assessment. With advanced diagnostic tools, they can pinpoint any problems and estimate remaining life. Even newer equipment can be using too much energy. The following pointers can help get you on the path to energy savings.
When making your home energy efficient, don’t forget to check the details. A Home Performance technician can help ensure you make simple, smart choices, helping you and your wallet breathe a sigh of relief.
ENERGY STAR website: “A Guide to Energy-Efficient Heating and Cooling”