Buying a New Furnace?

Last month we talked about whether you should consider buying a new furnace.  This month we provide some thoughts on how to buy a new furnace.  First let’s review some reasons you may want to consider a new furnace.

1. Your furnace is 20 years old or older.  
2. You are spending more on repairs.  
3. Your energy bills are going up.  
4. If you have to adjust your thermostat to maintain the same level of comfort.  
5. The furnace is making a lot of noise.  
6. It is cycling on and off more than it used to.
7. It has a pilot light.

Now here are some things to consider when buying a new furnace.

1. Size.  A furnace that is too small will not adequately heat your home.  That is kind of obvious.  So the natural inclination is to buy a unit that is larger than necessary.  But a furnace that is too big not only will cost more, but will also cycle on and off more frequently.  That can put more wear and tear on components, waste energy, and cause the temperature to fluctuate and reduce the life of the furnace.  So your best bet is to have an HVAC professional size your home, taking into account the climate and the size, design and construction of the house.
2. Efficiency.  How efficiently does the unit convert gas into heating energy?  This is measured by the Annual Fuel Efficiency Rating (or AFUE).  The higher the number the better, because that means the furnace is wringing more heat out of the gas it burns.  For homes in Chicago’s North Shore, a high AFUE of 90% or higher is recommended because of our harsh winters.  While units with higher AFUEs may cost more, in cold climates such as ours that additional cost can be recouped from lower utility bills.
3. Two-stage heating.  These furnaces control the flow of gas so that the furnace runs at low-fire during mild days and high-fire when it’s really cold out.  This allows the unit to operate more efficiently.  Additionally, furnaces with two-stage valves tend to be quieter.
4. Programmable thermostat.  A programmable thermostat allows you to pre-set the temperature.  That way, the temperature can be set lower when you are not home or sleeping.  You can save two percent on your energy costs simply by lowering the thermostat by one degree over eight hours.  Now there are thermostats you can control via a tablet or mobile device.  But a word of caution: make sure your thermostat is compatible with your furnace.  
5. Sealed combustion.  This protects your home from carbon monoxide poisoning.
6. Warranty.  Warranties vary, but look for a 20-year or lifetime limited warranty on the heat exchanger and 10-year limited warranty on all remaining components.  Your HVAC company may offer extended warranties.
7. Energy Star designation.  Furnaces with this designation meet Environmental Protection Agency (EPA) standards and reduce pollution by reducing energy 20% to 40%.