HVAC Efficiency Is the Name of the Game
Homebuyers and renovating homeowners are, now more than ever, interested in making sure their homes are as energy efficient as possible. And because climate control consumes the most energy in the home, HVAC systems are usually top of mind.
“Heating and cooling accounts for more than half of the energy use in a typical U.S. home, making it the largest energy expense for most homes,” the Department of Energy (DOE) says.
One way homeowners can reduce this energy use is by switching to a high-efficiency HVAC unit. Fortunately, the DOE and the industry have been working hard to increase and promote the energy efficiency of heating and cooling units.
New standards for central air conditioners took effect on Jan. 1, 2015. (The DOE also has proposed even more stringent standards to take effect in 2023, if approved).
The CleanEffects whole-home air cleaner charges and traps particles as small as 0.1 micron. It eliminates 99.98 percent of airborne particles at 0.3 micron and larger and reduces the need to dust by up to 50 percent, the company says.
The 2015 standards address regional differences for the first time. “The standards provide for a minimum cooling efficiency requirement of seasonal energy efficiency ratio (SEER) 14 for split-system central air conditioners in the South and the Southwest,” the Appliance Standards Awareness Project explains on its site. “For the North, the standard remains SEER 13 (the level that took effect for the nation as a whole in 2006). In the Southwest (a region comprised of Arizona, California, Nevada, and New Mexico), air conditioners must also meet an energy efficiency ratio (EER) requirement [that] helps ensure efficient operation at high outdoor temperatures. For heat pumps, the standard is the same in all regions: a SEER 14 and heating season performance factor (HSPF) of 8.2.”
Heat pumps are not subject to regional standards, however. The DOE says heat pump manufacturers (and importers) are responsible for ensuring that each model of heat pump distributed in the U.S. complies with all applicable federal energy conservation standards. But manufacturers have been developing innovative, energyeffi cient products on their own. For example, Bosch has developed hydronic air handlers that connect with tankless water heaters; they can be a clean, efficient alternative to conventional warm-air furnaces for providing effi cient heat (along with domestic hot water) for a home, the company says.
The company’s hydronic air handlers can be confi gured to work with AC systems, providing a complete heating, cooling, and hot water system. Two models can be sized with most CFM and BTU output ratings.
A hydronic air handler paired with a compatible condensing gas tankless water heater eliminates the need for the additional gas pipe, venting, and fresh air intake required by traditional furnaces. As the hot water from the tankless water heater circulates through the heating coil inside the hydronic air handler, warm air is sent through the duct system, says Freddie Molina, product manager at Bosch.
There are other ways to save energy. Green builders such as Matt Risinger have long argued that reducing the humidity in a house allows homeowners to run the AC at a higher temperature and still feel comfortable.
Whole-house dehumidifiers use a small fan and a refrigeration system to move air across condensing coils to remove excess humidity from the air in an entire home. They are rated by number of pints of water a day they can extract from the air. The units are ducted to the home’s HVAC system and plumbed into the system’s condensate drain.
The XT 105H whole-house ventilating dehumidifi er features MERV 11 air fi ltration and quiet operation. It can remove up to 105 pints of water daily, dehumidifying up to 2,500 square feet, and can be installed in a basement, attic, or crawlspace.
Builders and remodelers also should educate their buyers and clients about how a smart thermostat helps save energy. It allows users to monitor and control the temperature from a smartphone, tablet, or computer, enabling a variety of heating and cooling cycles to accommodate temperature preferences at various times. Installation consists of a hard-wired thermostat and sensors that monitor and control the temperature in different rooms.
This smart Wi-Fi thermostat is able to read temperature in multiple locations, solving for uneven temperatures. Wi-Fi connectivity allows remote control with a mobile device.
But the best HVAC system in the world will not lower the utility bills of a home with bad windows and poorly insulated walls. It also doesn’t help if occupants don’t have good energy-conservation habits.
As a construction professional, you need to build and renovate your houses with energy efficiency in mind, and homebuyers need to operate them with conservation in mind. A high-efficiency HVAC system will make a good house better, but it will do nothing for an inefficient one.
This story originally appeared in the May/June 2017 issue of PRODUCTS magazine. See the print version here.