A Homeowner’s Guide to Heating and Furnace Repair

This guide covers heating systems and types of furnaces, how to find a good furnace repair (HVAC) company, and common furnace problems.

Four Types of Furnaces

The furnace is the workhorse of a home’s heating system. Activated by a thermostat setting, the furnace generates warm air, which a fan propels into the ductwork for delivery throughout the house. The mechanics of the heat transfer depend on the type of furnace installed.

Oil Furnaces

Homes in the northeast United States commonly have oil furnaces. These units cost less than gas furnaces (they are up to 25% cheaper) but are a little less efficient. Cold air is heated as it goes through a heat exchanger. The warm air then travels through air ducts for distribution throughout the house.

Electric Furnaces

These furnaces cost much less than their gas counterparts (up to half as much) and last up to 10 years longer. However, they cost more per month to run because of the cost of electricity. Exposed elements heat air, which then travels through ducts to areas of the house.

Propane Furnaces

About 10% of U.S. households use propane-fueled furnaces. The propane is stored in aboveground or buried tanks. It ignites in the furnace’s burner. The heat is transferred to incoming air through a heat exchanger and then directed throughout the house.

Natural Gas Furnaces

Newer gas furnaces are very efficient and economical. About 50% of homes in the U.S. use these units. Gas furnaces use the same heat-transfer technology as propane furnaces.

About Heat Pumps

Many people are switching from traditional furnaces to heat pumps.

Heat pumps are ideal for homes in moderate climates and work by transporting heat energy to the outside or inside, depending on the season. In the summer, heat pumps remove heat from homes and channel it outside, acting as air conditioners. In the winter, they extract heat energy from the outside air and bring it inside, acting as furnaces. Although this does not seem intuitive, it works because of the heat energy present even in air that seems cold. In places with very cold temperatures, sometimes an auxiliary heating source is necessary.

Heat pumps consist of an indoor air handler and an outdoor heat pump. Like a traditional air conditioner, the heat pump contains a compressor.

The main difference between a heat pump and a gas furnace is the way in which the heat pump generates warmth. Heat pumps run on electricity and use power to transfer heat. Gas furnaces burn fuel.

Heat pumps are energy efficient and do not produce harmful emissions.

Choosing the Right Heating System

If you’re installing a heating and cooling system into a new home or are replacing an existing system, set up a consultation with an HVAC company representative. He or she will guide you through the process of selecting the type and size of system that is best for the home.

It is critical to install the right size of furnace or heat pump for your home. Too small, and the system won’t be able to keep up with demand. Too big, and you’re wasting money and efficiency. A consultant will help you factor in the size of the home, number of windows, household size, and local climate to determine the right size of unit.

Fuel sources available locally will influence the kind of heating system you settle on. Gas furnaces are more suited to some areas, while electric furnaces and heat pumps are better in other areas.

Reliable Furnace and Heat Pump Brands

Established and reliable furnace and heat pump brands include Trane, Rheem, American Standard, Carrier, and Goodman. Furnaces range in price from $850 to $2,550 depending on manufacturer, type, and size of system purchased.

Common Furnace Problems and How to Fix Them

Problem: The Furnace Isn’t Turning On

Is the thermostat on? Make sure it’s set to “heat” and the temperature is set to at least five degrees above room temperature. Check the furnace fuse in the breaker box and make sure it hasn’t blown.

Check the batteries in the thermostat and try changing them. Make sure the inside of the thermostat is free of dust and particles that could block connection points.

Is the heat on a timer? Look at the thermostat timer settings.

Check the safety switch on the furnace access panel door. If the door has been removed, the switch will pop out and prevent the furnace from running. The panel door must be closed with the safety switch latched for the furnace to operate.

Problem: The Furnace is Producing Less Heat Than Normal

Try changing or cleaning the filter. Clogged filters are the most common reason for sub-par furnace performance. A filter that is full of dust blocks air being drawn into the unit and forces the air handler to work harder than usual. The reduced airflow going through the system results in less warm air going into the house. Your electric bill might also increase since the air handler is having to work harder.

Intake filters can usually be found behind a grate in the wall, floor, or ceiling. Some are in the furnace itself.

Problem: The Furnace Runs but Doesn’t Produce Heat

Make sure the thermostat is set to “heat” and not to “cool.”

Check your breaker box for a blown fuse or a tripped circuit. The switch should be in the “ON” position. If it is in the “OFF” position, flip the switch back to “ON,” and this will reset the breaker.

Problem: The Furnace Burner Is Acting Up

The burners on gas or propane furnaces are vulnerable to clogging with dust and debris. Burner flames should be blue and even. If they are uneven or yellow, these are signs that the burner needs cleaning. Accumulated soot and condensation keep burners from performing properly.

Turn off the power and gas and then clean the burner with a vacuum cleaner. If you do your furnace maintenance yourself, make sure to clean the burner once a year, preferably just before the cold season starts.

Problem: The Blower Runs Continuously

This problem occurs when the limit switch is tripped. The limit switch is designed to trip when temperatures get too high. The flame or element turns off, and the blower runs to clear the heat. If a limit switch fails, it stays open, which means the blower will then run without stopping.

Call an HVAC company to have a technician come out and change the limit switch. He or she will determine if the blower running continuously is a limit switch problem or a thermostat that has gone bad.

Problem: The Furnace Turns Off and On Too Fast

This problem could arise for several reasons. One reason might be an old or dirty air filter. Clean or replace the filter, and if that doesn’t solve the problem, call an HVAC company. A technician will need to troubleshoot the issue.

Problem: Noises Come from the Furnace or Ducts

A properly functioning furnace should not have odd noises coming from the unit. There may be loose panels, bearings that have worn out, or motor belts that have slipped. Squealing or grinding sounds are signals that something isn’t right, and a technician should be called.

Popping noises in ductwork may be due to the ductwork expanding and contracting with changes in temperature. Pay attention to when the sounds occur, and you may be able to peg them to temperature changes.

Problem: There is a Smell of Gas

If you notice a strong smell of gas, call your gas utility provider and get all people and pets out of the house. Gas leaks are dangerous. Gas is combustible, so there’s a risk of explosion, and breathing in too much gas can be lethal.

How to Find a Heating and Furnace Repair Company

If you need to get the pros for heating and furnace repair, the provider to call is an HVAC company. HVAC stands for “Heating, Ventilation, and Air Conditioning.” HVAC companies provide all services related to temperature control, air distribution, and air quality in houses and buildings.

When it comes to heating systems, HVAC companies provide a variety of services, including:

furnace installation and replacement
furnace repair
heat pump installation and repair
maintenance of heating equipment

Find a Good Heating and Furnace Installation and Repair Contractor

Local friends, neighbors, and co-workers can be a great resource for finding a good HVAC contractor. Ask around for names and then follow up with your own research. Check out each contractor online and look for recent reviews. (We specify recent because old reviews may reflect a management style or team that has changed.)

Reviews on the contractor’s Google business page are quite reliable. The contractor cannot change these comments but can only respond to them. In contrast, testimonials on a contractor’s website are selected for the best display and can easily be written in-house.

Utilize service directories to find HVAC businesses near you. Try Angie’s List, Thumbtack, Home Advisor, and the Yellow Pages online, to name a few.

When you’ve found three solid companies, set up estimate visits for each one either for a repair or for maintenance service. Pay close attention to all aspects of the visit. Note the punctuality of the techs and whether they show company identification. Watch for thoroughness in work. Note attitude and conduct.

After all three estimate visits are complete, select one HVAC company to become your go-to heating and cooling service provider. Schedule the repair or the maintenance visit to make sure your system is performing optimally and positions you for an emergency-free heating or cooling season.