A furnace can keep running for decades, but not forever, and with age usually comes inefficiency. A homeowner with a 34-year-old furnace started a Reddit discussion and asked whether it made more sense to keep repairing it or replace it.

Here's what to know

In a Reddit post, the homeowner described a 1992 furnace that still works "fairly good" but needs its pilot relit about every couple of weeks. That recurring problem is becoming a real issue for a family with two children under 3, especially because the poster said they are often away for work and their spouse "refuses to turn it back on."

Commenters quickly moved beyond the pilot light itself and toward the main question: whether the furnace had been checked often enough to keep operating safely. One person asked, "When's the last time someone inspected the HEX or ran combustion on it?" The original poster answered, "Hex probably 5 years ago."

That issue raised the possibility that replacing one inexpensive part would not do much if the heat exchanger, combustion, or venting had not been inspected in years. One commenter boiled the advice down to this: "Get a new one."

Beyond safety, upgrading your heating and cooling system is also one of the best ways to save money on utility bills and protect yourself against rising energy prices. For homeowners weighing that decision, Palmetto's Comfort Plan network can help you find efficient heating and cooling solutions for your home and connect you with vetted installers, while helping homeowners understand their HVAC options and slash their energy bills with new, efficient HVAC systems and heat pumps.

More background

A furnace from the early 1990s likely predates many of the efficiency and safety features that are now common in newer systems. That doesn't automatically make it unsafe, but it does make inspection more important, especially when the unit already has an ongoing ignition issue and young children live in the home.

One commenter said a standing-pilot furnace is unlikely to be high-efficiency, and newer systems can waste less fuel, avoid some maintenance hassles tied to older ignition designs, and include more built-in safeguards. 

Another commenter endorsed the idea of replacement, saying, "Get a new one. The new ones have more safeties built in and won't have the pilot light. Not to mention you'll probably get more efficiency. Do it before it gets cold and the price goes up."

What can be done?

The common advice in the thread was to stop guessing at the next repair and replace the furnace. 

One HVAC contractor commenter said a qualified inspection can evaluate the heat exchanger, combustion performance, venting, gas pressure, and carbon monoxide risk, helping show whether a modest repair is still worth it or whether replacement is the better financial choice.

If replacement is the better option, efficient electric HVAC systems and heat pumps can lower operating costs. Palmetto appears here again for homeowners comparing options: if you're not ready to spend up front, the Comfort Plan includes $0-down options that can lower your heating and cooling costs by up to 50%. Palmetto Comfort Plans include 12 years of free maintenance.

Homeowners can also pair solar panels with electric appliances, like efficient HVACs, to drive their utility costs even lower. EnergySage makes it easy to find the best solar system and installer for your home and budget, saving you up to $10,000 on installations.

As one commenter advised, "Perhaps time to get a new high efficiency model."

Where can I learn more?

Older furnaces often leave homeowners weighing the same repair-versus-replace call. The articles below cover furnace breakdowns and what to weigh when comparing heat pumps with traditional systems.

• One homeowner ripped out the gas furnace and said the heat pump upgrade paid off.

• When an aging furnace quit, another homeowner questioned a heat pump upgrade before making the switch.

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