Dos and Don'ts in Purchasing a New Furnace

• Don't go with the lowest bidder

  "Service calls are twice as likely to be related to poor installation as to defective equipment. The guy with the lowest bid often makes the biggest mistakes."

• Contractor markup makes a difference

  "The heating contractor actually pays about $300 to $500 more for a 95 percent furnace than he does for a 90 percent furnace. So, if that added cost is passed through with little markup, you might be able to cost-justify it. If the contractor marks up the price a whole bunch, then you have no chance of making a payback in your lifetime."

• Have a pro install a new thermostat

  "Furnaces and thermostats, just like cars, have gotten increasingly computerized, and they can require some pretty serious know-how to get them to work right."

• High vs. very high efficiencies

  "Higher efficiency means higher complexity, and I like to keep the machinery as simple as possible. The more complex it is, the more expensive it is, and the more it will cost to fix when it breaks. Generally, your very best value is to get a 92 percent efficiency furnace with one of the new ECM fan motors."

• Get a proposal, not a bid

  "Go with someone who provides a detailed written proposal that outlines exactly what he will and won't do. He should list the manufacturer and model number of the proposed equipment as well as the cost of any plumbing, venting changes or electrical work required."

• Buy a reputable brand

  "Stick with the major brands or one of their subsidiaries. If you don't recognize the brand, don't trust what the contractor says about it. Do your own checking online before you buy."

• You may need a smaller furnace

  "Older furnaces were usually oversized so that the house was always warm enough. But new higher efficiency furnaces can have a lower Btu rating and still put out the same amount of heat. For example, a new 94 percent efficient furnace that is rated at 80,000 Btu puts out as much heat as an old 75 percent efficient 100,000 Btu furnace."

Source: Family Handyman