Is My Old Furnace Making Me Sick?
You may have noticed that your older furnace isn’t performing like it used to. If that sounds familiar, start by giving us a call at 503.223.8767, or send us a message:
It’s inconvenient if your furnace doesn’t consistently heat your home, but it’s outright dangerous if the furnace causes a fire or starts to leak carbon monoxide. In this article, we call out the main health and safety risks posed by older furnaces, including what to watch for and how to handle them.
How old is my furnace?
There are a few ways to find out how old your furnace is, depending on the brand, model, and serial number of your unit. Here are some steps you can follow:
Check the label or sticker
Look for a label or sticker on the furnace that has the manufacturer’s name, model number, serial number, and production date. This is usually located on the outside of the unit, or inside the cabinet or access panel. You can also check the manual or warranty documents if you have them.
Find the serial number
If you can’t find the production date on the label, you can use the serial number to decode it. Different manufacturers use different formats for their serial numbers, but they often include the year and week of manufacture. For example, a serial number that starts with 2024-03 means the furnace was made in the third week of 2024.
How does it look?
If your furnace looks old, it probably is. Don't sweat the details; just give us a call at (541) 330-8767. We’ll assess the condition of your furnace and make a recommendation that works for you and your budget.
What’s the expected lifespan of a gas furnace?
The average lifespan of a furnace is about 15 to 20 years, but that depends of a few factors, such as:
The type and quality of the furnace
Different types of furnaces have different lifespans. For example, electric furnaces tend to last longer than either oil or gas furnaces. The quality of the furnace also matters, as higher-end models from reputable brands tend to last longer and perform better than cheaper or lower-quality models.
The size and installation of the furnace
It’s important to have a properly sized furnace for your home, as a furnace that’s too big or too small can cause problems.
A furnace that’s too big will cycle on and off too frequently, which can wear out the parts and reduce efficiency. A furnace that’s too small will run continuously and struggle to heat your home, which can also damage the parts and increase energy consumption.
The installation of the furnace is crucial. A poor installation can affect the airflow, ventilation, and safety of the system. You should always work with a professional HVAC contractor [cough] like GreenSavers [cough] to install your furnace correctly and make sure you get the performance you expect.
The maintenance and usage of the furnace
One of the most important factors that affect the lifespan of your furnace is how well you take care of it.
Regular maintenance and inspections by a qualified HVAC professional can help extend the life of your furnace by keeping it clean, lubricated, and calibrated. Maintenance can also help prevent or detect potential issues before they become serious or costly.
What are the health and safety risks of an older furnace?
Fire hazards
One of the most serious risks of an old furnace is the possibility of a fire. According to the National Fire Protection Association, heating equipment is the second leading cause of home fires, and nearly half of them occur during the winter months. An old furnace can cause a fire in several ways, such as:
Leaking fuel: If your furnace runs on gas or oil, there is a chance that the fuel lines or valves may corrode or crack over time, resulting in leaks. These leaks can ignite if they come in contact with a spark or a flame, causing a fire or an explosion.
Overheating: If your furnace is not properly ventilated or cleaned, it can overheat and cause the components to melt or catch fire. This can also happen if your furnace is too small for your home or if you set the thermostat too high.
Combustible materials: If you store flammable items near your furnace, such as paints, gasoline, paper, or clothing, you are creating a fire hazard. These items can easily catch fire if they are exposed to heat or a flame from your furnace.
To prevent fire hazards, you should:
Have your furnace inspected and serviced by a professional at least once a year, preferably before the heating season starts.
Replace any worn or damaged parts, such as fuel lines, valves, filters, belts, or wires.
Keep the area around your furnace clear of any combustible materials and leave at least three feet of space between them and your heating equipment.
Install smoke detectors and carbon monoxide detectors in your home and test them regularly.
If you smell gas or see smoke coming from your furnace, turn it off immediately and call 911 or your utility company.
Carbon monoxide poisoning
Another serious risk of an old furnace is carbon monoxide poisoning. Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is produced by the incomplete combustion of fossil fuels, such as natural gas, oil, or wood.
If your furnace is not burning properly or if the exhaust vent is blocked or damaged, CO can leak into your home and build up to dangerous levels. CO can cause a range of symptoms, such as:
Headache
Dizziness
Nausea
Fatigue
Confusion
Loss of consciousness
Death
To prevent carbon monoxide poisoning, you should:
Have your furnace inspected and serviced by a professional at least once a year, preferably before the heating season starts.
Install carbon monoxide detectors in your home and test them regularly.
Make sure your furnace has a proper venting system that is free of cracks, holes, or obstructions.
If you experience any symptoms of CO poisoning, get out of your home and seek medical attention immediately.
Improper venting of furnaces is one of the biggest culprits we see. It’s a potential huge contributor to CO in homes, especially for some of these older 'pre-code' furnace installations.
Here are some of the biggest no-nos that we see with improper furnace venting:
Improper Slope for B-Vent:
The B-vent, which carries exhaust gases from the furnace, must be installed with the correct slope. If the slope is inadequate, it can lead to poor airflow and inefficient venting.
Proper slope ensures that combustion byproducts are effectively expelled from the home, reducing the risk of CO buildup.
Use of Improper Materials:
Some homeowners use materials other than B-vent for furnace venting. This is a major mistake.
Only approved B-vent materials should be used to ensure safe and efficient venting. Using non-approved materials can compromise the system’s integrity and lead to CO leakage.
Improper Sealing of B-Vent Connections:
Properly sealed connections between the B-vent and the chimney or vent stack are crucial.
Inadequate sealing can result in exhaust gases leaking into living spaces, posing health risks to occupants.
Orphaned B-Vent Connections:
“Orphaned” B-vent connections occur when a furnace is replaced, but the old venting system remains in place.
These abandoned connections can disrupt airflow, leading to poor exhaust ventilation and potential CO accumulation.
Breathing problems
A third risk of an old furnace is breathing problems. An old furnace can affect the indoor air quality of your home by releasing dust, dirt, allergens, and other pollutants into the air. These particles can irritate your respiratory system and cause or worsen conditions such as:
Asthma
Allergies
Bronchitis
Sinusitis
Pneumonia
COPD
To prevent breathing problems, you should:
Have your furnace inspected and serviced by a professional at least once a year, preferably before the heating season starts.
Replace or clean your furnace filter regularly, according to the manufacturer’s instructions.
How can I choose the best furnace replacement for my home?
If you have an old furnace in your home, you may be wondering whether you should replace it with a new, efficient gas furnace or a heat pump. In general, a new, efficient gas furnace is better than an old furnace, but a new heat pump is the best option for most homeowners in Oregon.
Heat pumps cost less to operate and produce significantly less greenhouse gas emissions compared to gas furnaces. We’ll go into a bit more detail about why we recommend heat pumps in most cases:
Heat Pumps Have Lower operating costs
Heat pumps are more energy-efficient than gas furnaces, as they use less electricity to move heat than gas furnaces use to create heat. Check out our articles for the details. At a glance:
| Ducted Heat Pump | Mitsubishi SVZ Heat Pump | 305% (10.4 HSPF) | Electricity (kWh) | $533 | $2,235 |
| Gas Furnace | Rheem Prestige Series Gas Furnace | 95% (95% AFUE) | Natural Gas (Therms) | $682 | $0 |
Heat pumps have fewer moving parts and require less maintenance and repairs than gas furnaces. They also have a longer lifespan than gas furnaces, typically lasting 20 to 25 years, compared to 15 to 20 years for gas furnaces.
Heat Pumps Have a Smaller Carbon Footprint
Heat pumps have a lower carbon footprint than gas furnaces, as they use electricity from renewable sources, such as solar, wind, or hydro power. It’s estimated that upgrading from a furnace with 96% efficiency to a heat pump can lead to a substantial decrease in CO2 emissions, potentially between 76% and 81%.
Which furnace repairs do you need, and does it make sense to repair or replace your furnace? Give us a call at 503.223.8767, or send us a message.
Learn More About Heating and Cooling
Start by visiting our heating and cooling resource pages for homeowners in Portland or Bend, Oregon. You can also keep reading our latest blog articles about energy efficient heating and cooling.
