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How Long Should My Furnace Last?

furnace replacement

How long do furnaces last?

Most people don’t know that 95% of furnaces out there are not going to last much more than 20 years. Anything past 20 years and your furnace are likely operating on borrowed time. The warranties from the builder of those furnaces were made with 5-year parts warranties, so even they were only thinking 10, 15, maybe 20 years. I get asked that question a lot. How long should my furnace last? I tell them most furnaces last about 20 years.

Can furnaces last longer than that?

It is true that we run across service calls on systems that have safely made 35-40 years.  So, it can happen! As long as the parts are still available to make repairs that allow the machine to operate at or above original factory specifications. Also, if the system is still safe to operate, meaning the fire box or heat exchanger is NOT cracked, potentially releasing carbon monoxide through the supply registers in your rooms, it’s safe to operate. Fox Family techs take a special class every year to ensure we are capable of inspecting any heat exchanger to ensure the safety of your family.

Maintain your furnace

If the furnace is maintained properly over the years, like mine, the furnace can easily last 20 years. Sure, some things may break along the way, but a properly trained HVAC technician can get your furnace up and going again. Some other major parts that can break on a furnace are the inducer motor, blower motor, gas valve, and control board. Some of the minor repairs are the pressure switch, capacitors, ignitors, roll-out and high limit switches.

How do I know my furnace is not working?

Inducer Motor

An inducer motor that doesn’t work is going to cause the flame and its exhaust not to shoot into the furnace the proper way. This can cause a serious safety issue in the home. Fortunately, there are safety switches all along the firing up sequence to make sure this doesn’t happen. The control board knows what should work and when it should be working. It’s a very intelligent furnace that has been made over the last 20 years.

Blower Motor

Another component that the furnace can tell is not working is when the blower motor stops working. The blower motor pulls the air from the room and pushes that air through the hot furnace and into your rooms. It’s supposed to be running at a very specific speed. If the blower is running too slow, or not at all, the furnace will overheat. This lets one of the safety devices in the furnace to sense the high heat and shut the system down.

Gas Valve

The gas valve is another major component that must be checked on a regular basis. It’s responsible for emitting the proper amount of gas to the burner assembly which shoots the flame into your heat exchanger. The gas valve is capable of getting stuck in the open position too. Sometimes we get calls where the homeowner is smelling gas in the house, or near the furnace. We have come in to diagnose the system and found that the valve is actually stuck in the open position, albeit ever so slightly. This is obviously a dangerous situation to have. An odorant is added to natural gas and propane gas to help homeowners/customers sniff out leaks. If you smell gas, and no stove burners were left on, evacuate the house and call 9-1-1. Then, call your natural gas provider (your utility).

Control Board

Finally, the control board is one of the major components of your furnace that can go out. If it does, the system just won’t know what to do and when to do it. The control board is the brains of the system. The symptom I see the most on controls boards that have failed is when the solder connections on the back of the board have started to fracture. They started out as complete solder points relaying signals to other parts of the board. But these fractures make it difficult to send the electronic signal. This causes a slow and sometimes very annoying failure of the system because sometimes the system works and sometimes it does not. Maybe in the mornings, it will work but in the afternoon it does not. This usually indicates something is wrong with the furnace control board. Not always, but in my experience has been a good place to start.

Make sure you are getting the proper maintenance done on your HVAC system so it can last up to 20 years. If you don’t, chances are you will be replacing your furnace sooner, because of neglect, just like your car. Let Fox Family come out and get your furnace tuned up for the season every year. My system is so perfectly clean and functional year after year because I clean it and check all the components every year. My system is 19 years old this year too!

Fox Family Heating & Air serves Sacramento, Rancho Cordova, and all of Northern California. If you’re looking to schedule HVAC service in these areas, give us a call!