A furnace repair can be the right choice one year and the wrong choice the next. In Minnesota, where a furnace runs for most of the year, the decision also affects your comfort and safety through a long winter. Use the factors below to decide whether to repair your current furnace or plan a replacement.
Start with the furnace's age
Age is not the only factor, but it sets the context for every other one. ENERGY STAR's guidance on when to replace heating and cooling equipment suggests considering a new system if your furnace is more than 15 years old.
To find the age, look for the rating plate inside the furnace's front panel or on the side of the cabinet. The serial number often contains the manufacture date, but each brand codes it differently. Your home inspection report or the original installation paperwork may also list it.
A younger furnace with a single failed part is usually worth repairing. An older furnace that needs a major part deserves a closer look at replacement.
Look at the type of repair
Not all repairs are equal. Some parts wear out on a normal schedule and cost little to replace compared to the value of the furnace. Others are major components.
Repairs that often make sense on a furnace in good condition:
- Flame sensor cleaning or replacement
- Hot surface igniter replacement
- Thermostat repair or replacement
- Pressure switch, limit switch or control board replacement
- Clearing a clogged condensate drain on a high-efficiency furnace
Repairs that should start a replacement conversation:
- A cracked or failed heat exchanger
- A failed draft inducer motor or blower motor on an older furnace
- A failed gas valve on a furnace near the end of its service life
- A second or third major repair in a short period
Ask your technician whether the furnace is still under the manufacturer's parts warranty. Coverage can change the math on a major part, and registration terms vary by brand.
Weigh safety first
Some problems are not a repair-or-replace choice. They are a safety issue. A cracked heat exchanger can let combustion gases, including carbon monoxide, mix with the air circulating through your home. If a technician finds a crack, they may shut off the furnace until it is repaired or replaced. Do not restart a furnace that a technician has tagged as unsafe.
If your carbon monoxide alarm sounds or anyone in the home has headaches, dizziness or nausea that improve when they leave the house, get everyone outside and call 911. If you smell gas, leave the house right away, do not use light switches or phones inside, and call 911 and your gas utility from outside.
Consider comfort and efficiency
A furnace can still run and still not do its job well. ENERGY STAR lists these signs that your heating system may not be working as it should:
- Frequent repairs and rising energy bills
- Some rooms are consistently too hot or too cold
- Air that is too dry in winter
- Excessive dust in the home
- A noisy heating system
Older furnaces are often 80% AFUE or lower. AFUE is the share of the fuel's energy that becomes heat in your home. Newer condensing furnaces are rated 90% AFUE or higher. Over a long Minnesota heating season, that difference shows up on your gas bill. A replacement also lets you correct sizing problems, add a variable-speed blower, or add whole-home humidification.
Check incentives and timing
Incentives can change the cost of replacement, and they change over time.
- Federal tax credit: The federal Energy Efficient Home Improvement Credit covered qualifying furnaces through 2025. According to the IRS page on the Energy Efficient Home Improvement Credit, it applies to improvements made through December 31, 2025. A furnace installed in 2026 does not qualify.
- Utility rebates: CenterPoint Energy offers rebates to Minnesota residential customers for qualifying high-efficiency furnaces. Its heating system rebates page lists the AFUE tiers and deadlines. For 2026, equipment must be installed and the application submitted by December 31, 2026.
Timing matters too. If your furnace is old and showing several warning signs, replacing it in the fall lets you compare options. Replacing it after a breakdown in January means making a decision while your home is cold.
Questions to ask before you decide
Write down the answers when your technician explains the problem:
- What failed, and why did it fail?
- Is anything else close to failing?
- Is the part covered by a manufacturer's warranty?
- Is the furnace safe to run after the repair?
- If I replace it, what size and efficiency would you recommend, and how did you determine the size?
- Would a new system need venting, gas line or electrical changes?
A good technician will answer these plainly and show you the failed part when possible.
When to call a professional
Call for service if your furnace will not heat, cycles on and off often, makes new noises, or needs frequent resets. If your furnace is more than 15 years old and needs a major part, ask for both a repair quote and a replacement estimate so you can compare. Krinkie's handles furnace repair and furnace installation, and offers 24-hour emergency service when your heat goes out.
Common questions
How old is too old for a furnace?
ENERGY STAR suggests considering replacement when a furnace is more than 15 years old. Age alone is not a reason to replace a furnace that runs safely and well, but it matters when a major repair comes up.
Is a cracked heat exchanger worth repairing?
A cracked heat exchanger is a safety problem because it can let combustion gases into your home's air. On an older furnace it usually leads to replacement; on a newer one, ask whether the heat exchanger is under the manufacturer's warranty.
Can I still get a federal tax credit for a new furnace?
No, not for a furnace installed in 2026. The IRS says the Energy Efficient Home Improvement Credit applies to improvements made through December 31, 2025. Check your gas utility for current rebates.