Living Smart: A primer before you buy a new furnace

McClatchy-Tribune Information Services

This time of year, your home heating system may be going through the occasional warm-up lap or it could be in full-blown workout mode already.

Hopefully, your system is fit for winter duty. But if you have doubts, hereís advice from top-rated HVAC pros:

To assess your current system, ask your HVAC contractor to provide a written efficiency analysis and summary of any recommended repairs. Your contractor can do this during an annual tune-up.

Heating systems are not one size fits all. Be wary of a contractor who offers a quote without examining your home. Ideally, a technician should perform whatís called a "Manual J calculation," which includes square footage, window efficiency and other factors to determine the right size heating system. An incorrectly sized system will cost you money and comfort.

Buy the most efficient furnace you can afford. Efficiency ó a measure of how much energy put into the furnace is converted into heating power ó is described in terms of AFUE (Annual Fuel Utilization Efficiency). The federal government requires that most types of furnaces reach a minimum 80 percent AFUE, though some models can achieve as much as 97 percent AFUE.

Depending on where you live, you may have several fuel choices:

Natural gas, considered the most economical way to heat a home when temperatures are below freezing.

Oil or propane, which can be a good option where gas lines arenít available. However, oil or propane furnaces require more storage room, run "dirtier" than natural gas and can be more expensive to operate.

Electricity, which can be an expensive way to fuel a furnace. Often, a heat pump is a more economical option for an all-electric house.

A heat pump, which transfers heat from one source ó the air or ground ó to another, also acts as an air conditioner in summer. One heat pump type, called ductless mini-split, can be a good alternative for homes currently heating with electric baseboards or wall heaters.

Keep in mind, however, that on very cold days, a heat pump may not perform as well as other systems. Thatís why contractors typically suggest keeping your gas or oil system as a backup.

If you experience hot and cold spots in your home, or are using too much energy to keep your home at a set temperature, you may benefit from a zoned system. Zoning divides a home into areas, each controlled by a separate thermostat, and can help you save on utility bills, reduce wear and tear on your system and increase indoor comfort.

The cost of a new heating system can vary widely, depending on equipment type, your homeís layout, desired features, local labor costs and any necessary changes to existing system components.

A general price range would be $4,000 to $8,500 for a heating and air conditioning system with basic installation and features. Additional features will add to the cost, and include air purifying systems, new insulated ductwork, humidifiers, programmable thermostats and more.

Seek multiple bids from HVAC contractors who are appropriately licensed, insured and bonded, and who have positive consumer reviews on a trusted online site.

Keep in mind that November through March is the busy season for heating contractors. You might get a better deal if you seek bids between April and October. Also, check with your local utility or HVAC contractor to see if you qualify for incentives or rebates.