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Serving The Greater Fresno Area Since 1970

Serving The Greater Fresno Area Since 1970


Donald P. Dick Air Conditioning Blog

How To Handle A Red-Tagged Furnace

Homeowners who hear that they have a red-tagged furnace may not like the news, but at least they can avoid the serious consequences that the condition may create if left untended. A furnace that receives the red tag, or a document meaning the same thing, usually has a cracked heat exchanger that may emit carbon monoxide (CO) into the home, an odorless and colorless gas that is deadly in sufficient quantities.

The HVAC contractor who finds a crack has to disable your furnace because of the dangers of CO poisoning. The two options you’re faced with are replacing the heat exchanger or the furnace. If your furnace is still under warranty, replacing the heat exchanger may be the best choice.

When your furnace is older and the warranty has expired, replacing it rather than repairing it may make more economic sense. Spending a good deal of money fixing an aging furnace may not be a good use of your money, since newer furnaces offer much better efficiency, which lowers your heating bills. A furnace replacement may happen quicker than a heat exchanger repair, and the new system will have an active warranty.

It’s also a good idea to get a second opinion before committing to either a repair or replacement for a red-tagged furnace. NATE-certified HVAC contractors bring the most expertise, since they have to pass rigorous testing and performance to keep their credentials valid. This is important when diagnosing a crack in the heat exchanger.

The process is not always straightforward because the part may be hidden from view. Sometimes HVAC technicians use hand-held CO detectors, flashlights or inspect the flame. A flame that burns yellow can indicate problems with cracks in the system. Harmless smoke bombs can show leakage, as can special gases or sulfur, an easily detected odor.

If you would like more information about a red-tagged furnace, contact Donald P. Dick Air Conditioning. We’ve provided quality HVAC services for the Central Valley for more than 40 years.

Our goal is to help educate our customers in the greater Fresno, California area about energy and home comfort issues (specific to HVAC systems).  For more information about Red-Tagged Furnaces and other HVAC topics, download our free Home Comfort Resource guide.

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