Most homeowners live in areas that experience extreme weather. HVAC equipment operation can account for as much as 50 percent of your home’s total utility costs. Maximizing energy efficiency is critical for reducing operating expenses and extending the life of your heating and cooling system.
The Critical Role of Capacity
Since it is a relatively technical concept, the relationship between operating costs and equipment capacity is often misunderstood. However, there is no factor more important in determining the efficiency of your HVAC system. Contractors that do not run a complete set of load calculations before selecting equipment may significantly miscalculate the size of the unit required to properly heat and cool the living area. Two buildings of identical size may have entirely different internal loads, depending on quality of the materials and installation techniques used in the construction process.
In order to compensate for inaccurate load estimates, many contractors purposely choose to oversize the system. Unfortunately, excess capacity will cause the equipment to short cycle. This condition negatively impacts unit longevity and severely degrades system efficiency. Homeowners are encouraged to verify that the installing contractor will run a complete set of Manual J load calculations before purchasing new HVAC equipment.
Maximizing Energy Efficiency
Energy efficiency upgrades usually provide an excellent return on investment. Over time, most improvements actually pay for themselves. Efficiency enhancements also provide additional benefits such as better temperature and humidity control, lower noise levels and a longer equipment lifecycle. Here are some of the most cost effective efficiency improvement strategies.
* Equipment Replacement: Replacing aging or obsolete heating and cooling equipment can offer significant benefits. A 17 SEER air conditioner can save up to 41 percent on monthly utility costs when compared to a 10 SEER unit. A 95 AFUE rated furnace is 15 percent more efficient than an 80 AFUE rated appliance installed in the early 2000s. A new replacement system will also help reduce repair and maintenance costs.
* Low-E Windows: Low-E windows incorporate a metallic-oxide coating into the manufacturing process. The coating is placed on an interior surface in a dual-pane configuration to help reject UV and radiant energy in southern climates and retain heat energy in northern climates. Low-E windows have an exceptional thermal conductivity rating and will help reduce infiltration around the window frame. Low-E windows can save up to 35 percent on annual HVAC operating costs.
* Routine Maintenance: Regular furnace and AC maintenance helps keep your heating and cooling system performing at peak efficiency. Trained technicians inspect key components to identify minor problems before they can cause an unexpected breakdown. Other important services include clearing the drain lines, checking refrigerant levels, lubricating motors and bearings, cleaning the coils and calibrating the system. Run time hours are reduced, which helps lower operating costs and decreases accumulated wear on vital parts.
* Programmable Thermostats: Modern programmable thermostats use smart technology to analyze the occupants’ living habits and develop programs that optimize energy usage. When the building is empty, the temperature is raised to maximize savings. When the unit anticipates someone is on the way home, the temperature is gradually adjusted to the desired comfort setting. Proper use of programmable thermostats can save up to 30 percent on your HVAC related utility bills.
* Duct Sealing: Homes built before the mid 2000s usually have significant duct leakage that reduces HVAC system efficiency. In certified testing, some homes were found to lose as much as 50 percent of the air generated at the blower because of duct leaks, gaps and loose connections. Negative pressure leaks are particularly damaging since they draw dirt, dust and other contaminants directly into the living area. Trained professionals have the equipment and expertise to seal the ductwork from the inside of the system, which will help improve comfort and efficiency.
* Insulation upgrade: Of all the available energy efficiency investments, insulation remains the best value. It is relatively inexpensive and contains no moving parts to break down. Many homes built prior to the mid 2000s have substandard levels of insulation. If your home does not comply with current Department of Energy standards, an attic insulation upgrade is highly recommended.
* Perimeter Sealing: Unplanned air infiltration robs your HVAC system of efficiency because the unit must work longer to satisfy the indoor load. Caulking and sealing plumbing penetrations, electrical penetrations, window frames, door frames and the sill plate will help reduce drafts and save energy.
A Few Inexpensive Ways to Improve Efficiency
An energy efficiency strategy includes structural improvements and practical changes in living habits. You can save up to four percent on heating and cooling costs for every degree you raise the thermostat in the summer or lower it in the winter. Consider planting trees close to the house to provide a thermal break, and always remember to change your furnace filter every month.