By Andrew Lake Currently, most homes do not have high efficiency furnaces. Most homes are equipped with 60% efficient 80’s era furnaces or 80% efficient 90’s era furnaces. They only move 60-80% of the heat they create into your home. The other 20-40% is lost up the chimney. This is because the exhaust gases are released at temperatures higher than the boiling point of water. This is so that the water produced when natural gas is burnt does not turn into a liquid and rust the furnace and chimney.
New high efficiency gas furnaces have a second stainless steel heat exchanger. All of the heat is removed from the exhaust gases and transferred into your homes air. This results in 90-95% of the heat produced being used to heat your home.
A furnace does not just consume gas. The blower’s electric motor is probably one of your homes largest consumer’s of electricity. Some new models of furnaces are equipped with variable speed motors. They are also known as ECM or brushless DC motors. The average standard motor consumes about 400 watts of electricity when running in heating mode and 300 watts in circulation mode. The average variable speed motor will only consume about 60% as much energy in heating mode as a standard motor. They use only 10% as much power in circulation mode compared to a standard motor. Homeowners who run the fan continuously to circulate the air for freshness and a summer cooling effect can save over $100 a year with a variable speed fan.
Continuously running a variable speed fan can also result in more even temperatures from room to room within the house.
Most manufactures offer a basic 90% efficient high efficiency furnace and a premium 94-95% efficient model with a variable speed fan and very quiet operation.
Andrew Lake is a licensed heating and air conditioning technician with Shell Busey’s HouseSmart Heating and Air Conditioning in Vancouver, Canada.
Energy Boomer’s comments: Using the furnace fan to continuously circulate air in a house is like running invisible ceiling fans. It has the added advantage of filtering the air as it circulates the air. The result is more comfort and some energy savings by having an even temperature through out the house. It is a real money saver if you can avoid air conditioning just by moving the air for comfort.
The next article in this series will be an in depth look Air Source Heat Pumps.
Click here for a free money saving report written by the Energy Boomer titled HOW SAVE MONEY ON YOUR NEXT HEATING BILL