Should You Repair Or Replace Your Gas Furnace?
It inevitably happens with every old furnace, you wake up on a freezing winter morning and your bedroom is ice cold. You turn the thermostat up, but there's nothing but silence. Your furnace has stopped working. If you're lucky, it's a simple, inexpensive fix. But if the furnace is getting up in years and needs extensive repairs, how do you decide if the advantages of installing a new furnace is a better solution than repairing the old unit and hoping it lasts through another long winter?
How long does a gas furnace last?
A 2007 study by the National Association of Home Builders found that gas furnaces last an average of 15 to 20 years. So consider the age of the unit when deciding whether to repair or replace. When a furnace is installed most technicians will write the year the equipment was installed right on the unit. You can also look for a metal identification plate, usually on the inside of chamber door (be sure the unit is off and cool before checking inside). Record the model and serial number, then call the manufacturer’s customer service number to obtain the date of manufacture
Furnace Repair Costs
If the furnace is beyond three-quarters of its life expectancy and repairing it would cost a 1/3 or more of the amount of a new furnace, it may be more economical to replace the unit.
Comparing Energy Savings
In these days of high fuel costs, it's important to consider is the efficiency of the old furnace versus a newer unit. A standard measure of fuel efficiency is the Annual Fuel Utilization Efficiency number (AFUE). AFUE measures the percentage of the fuel that’s converted to heat rather than being lost through inefficiency.
If the furnace is 20 or more years old, its AFUE is probably about 70. New furnaces will have an AFUE of at least 80%, which means you’ll burn 10% less fuel, that's 10% savings of your heating bill. High efficiency furnaces go as high a 95% AFUE , which could save you 25% on your heating bill.