Heating, cooling have gone high-tech

It wasn't so long ago that a person could call a contractor, replace an entire home heating and air conditioning system and forget about it for the next 20 years, except for periodic cleanings and maintenance checks.

Those days are long gone. Today's residential heating and air conditioning units have so many different operating parts that there is more of a chance for something to break down. Sure they are more energy efficient, but the trade off comes in the homeowner having to be more knowledgeable about what systems will fit inside a home as well as more vigilant in maintenance to ensure that everything is working properly.

"It used to be that furnaces would last 20, 30 years," said Bill Semitekol of Duo-Temp Inc. in Elk Grove Village, who's also the executive director of HISA, a state association for heating, ventilation, air conditioning and refrigeration professionals. "Because of all the components that they (manufacturers) put in to make them more energy efficient, the units are only lasting 10 to 12 years."

Government mandates are the cause of this muddied picture. The Montreal Protocol, an international treaty designed to protect the ozone layer, requires phasing out of refrigerants that deplete ozone via a specified timeline. Couple that with requirements making both heating and cooling units more energy efficient, and you have a quagmire in which the consumer can easily get stuck.

"It's definitely in the consumer's best interest to do as much research as possible," said Mark Lowry, vice president of RSES, a national society dedicated to educating and training heating and air conditioning professionals. "Since 2006 these systems have skyrocketed in cost. In the old days when a condenser went out, you could replace just that. Now you have to replace the whole unit."

What happened in 2006 was enactment of a federal mandate requiring climatization systems to become 30 percent more efficient. In essence that made many older systems, even those installed only several years earlier, obsolete. Plus, in the case of furnaces, trying to fit a heating unit into an older system could even become dangerous.

"One of the weirdest things is we get people who want us to give quotes over the phone," said Chris Colditz of Laco Mechanical Systems Inc. in Elk Grove Village. "There are just so many hidden issues in each home that it's no longer feasible to say bring a universal furnace and we'll make it work."

What is needed is a thorough inspection of your home's current heating, air conditioning and ventilation system, including placement of the mechanical units as well as the home's square footage and architectural features. Because of the nuances of each installation, both Colditz and Semitekol indicate homeowners should not be fiercely loyal to any particular manufacturer. With the exception of Trane, all of the other major manufacturers use the same compressors, so except comparable units to be similar. Expect cost to replace heating and air conditioning units to run between $3,000 and $12,000 depending on the size of your home and optional features included.

But even before you contact contractors for quotes, there are several things you can do to make sure that your heating and air conditioning units will operate at peak efficiency.

RSES' Lowry recommends homeowners get a home performance assessment and load calculation to determine heat loss and gain.

"It takes about a half-hour to an hour to do the measurements, which include temperature and airflow," Lowry said. "It's reasonably complex."

These inspections take into account how the building envelope is performing as a whole unit. All renovations since the current systems were installed need to be noted, including installation of new windows, which is wonderful for energy efficiency but negatively affects ventilation and indoor air quality. Once you have those calculations you can present them to contractors you contact for the potential job.

"Those calculations have to match the components so the furnace installed is properly sized," Lowry said.

A properly sized furnace, as well as air conditioning unit is important on several fronts. Particularly with furnaces, the size of the unit is directly tied to your home's needs. Installing an improperly sized unit can lead to unsafe conditions, which sometimes leads to operational shutdown because of the safeties built into new systems. Secondly, if a system is improperly sized, it will not operate at peak efficiency.

The latter speaks to problems homeowners may encounter with new construction. Just because your unit may only be a few years old doesn't mean it's doing the job. Lowry noted that contractors of track developments, in particular, use a cookie-cutter approach in purchasing and installing heating and air conditioning units, buying them in bulk to keep down the purchase price of the house. While the unit in question may still technically be OK, it may not have the proper fit for your home.

Once your home's needs have been assessed, it's time to select the units.

"Everyone wants a 90 percent efficiency furnace, but that's not always practical because of the variables," Colditz said. "I'm going to give you a choice of units that are going to work with your site."

For furnaces, you have a choice of single stage, dual stage and dual stage variable speed units. In a single stage unit, all the burners ignite every time the furnace turns on regardless of outside temperatures. In a dual stage unit, only 60 percent of the burners turn on initially. If the thermostat is not satisfied within a short period, the rest of the burners turn on. Dual units save homeowners gas and energy costs. Dual stage variable units act much the same as regular dual stage units, but are augmented by the latest blower technology, resulting in further cost savings.

In addition to the base unit, your quote may contain recommendations for add-on items to improve safety and energy efficiency.

"People need to have a digital carbon monoxide detector in their homes because small infants and older people can't tolerate the same levels of the gas as others," Semitekol said.

In addition to carbon monoxide detectors, air cleaners are another add-on that helps insure your home has sufficient air exchange with the outdoors. On the comfort side of the coin, a humidifier will help keep your home feeling warmer by injecting water into the air during dry winter weather.

"People think they're saving money by not installing a humidifier," Colditz said. "But you know how humidity makes you feel uncomfortable in summer because it makes you feel warmer?" It makes you feel warmer in winter, too, so you can turn down your thermostat.

Selection of an air conditioning system is similar, as there are single and dual stage units that operate on the same principle as single and dual stage furnaces. In order to have a two-stage condensing unit, you must have a two-stage or two-stage variable furnace. With air conditioning systems, however, you will be faced with SEER ratings and selection of refrigerants.

SEER is an acronym for Seasonal Energy Efficiency Rating. As of January 2006, all air conditioners sold in the US must have a minimum SEER rating of 13. Higher efficiency units can have a rating has high as 21. But do the higher rated units save more money? Not necessarily.

"SEER ratings are only comparable for running at peak loads," Semitekol noted. "You'll only save money with a higher SEER rating if you run your air conditioner all the time and very few people do that."

Also of note is selection of units that use R22 or Freon versus 410A or Puron refrigerants. Manufacture of units using Freon will be phased out by 2010, making them obsolete.

In addition to selecting properly sized systems for your home, correct installation is critical.

"A bad installation can take so much efficiency out of a good system," Colditz said. "If you're short even ¼-pound of refrigerant, you're short on efficiency."

Another danger is installation by do-it-yourselfers or handymen. Many people still think they can buy a unit and install it themselves, but the variables that go into installation make that a risky proposition.

"Illinois is a state, in particular, that has a lot of companies claiming that they are qualified to handle heating and air conditioning installation when they are not," Lowry said. "Make sure that the contractor you use belongs to industry association and has installers who have gone through training."