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MarGo Plumbing Heating Cooling Inc. Blog

Is It Worth It to Fix an Old Furnace? How to Know When to Replace It


Maybe it’s been a while since you’ve thought about your furnace. After all, you haven’t needed it all summer! But it’s best to consider it now, so you can get any repairs done—or schedule replacement if necessary—before you’re left with a freezing home in January, trying frantically to get someone to come to fix or replace your furnace in a hurry. How can you tell if furnace repair or system replacement is the right choice? Here are some key things to weigh while you make that decision. 


This is the most critical factor. A gas furnace can be expected to last for fifteen years, and an electric furnace for more like twenty, provided you’ve been diligent about annual maintenance. If your furnace is already past that age, no repair is likely to keep it running for long. 


A well-maintained furnace should keep running well with only occasional repairs for the full extent of those lifespan estimates. But a neglected furnace might only survive half that long, so if you’ve never had maintenance done, consider your ten-year-old furnace to be at the end of its life. You can also look at the furnace itself. Visible corrosion is a sign of poor condition or possible serious problems.

Frequency of Repair Needs

With maintenance, a furnace should need repairs only on rare occasions. If you need furnace repair now, and you’ve needed it within the last year or two as well, it’s likely that completing this repair will just lead to a short window of furnace functionality followed by more repair needs. Don’t forget that even if each repair is affordable, these costs add up.

Cost of Repair

If you know that a repair would be necessary to get your furnace up and running for winter, you should weigh the cost of that repair and the age of the furnace and consider whether replacement would be a better investment. There are a couple of ways to do this. One recommendation is never to invest in a repair that would be more than half the cost of replacing the furnace. Another is slightly more specific: the 5000 rule.

Multiply the estimate of the repair cost by the age of the furnace, and if your result is over 5000, replace rather than repair. For example, a $500 repair on an eight-year-old furnace yields a result of 4000, suggesting that the repair is a reasonable choice. That same $500 repair on a twelve-year-old furnace would give you an answer of 6000, indicating that replacement is likely a better investment. 

To get a clear and specific assessment of your old furnace in Livingston, NJ, have it evaluated by a qualified professional who can give you an accurate idea of the overall condition it’s in as well as an estimate for the repairs it needs. Don’t hesitate to ask questions: we believe that the most satisfied customers are the ones armed with the knowledge they need to make decisions they’ll be happy with for years to come. 

Contact MarGo Plumbing Heating Cooling Inc. today for more information about your furnace repair and replacement options!

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