{"id":4428,"date":"2019-05-14T16:54:00","date_gmt":"2019-05-14T20:54:00","guid":{"rendered":"https:\/\/a1mechanical.imarketbeta.com\/blog\/?p=4428"},"modified":"2026-09-17T06:39:44","modified_gmt":"2026-09-17T10:39:44","slug":"why-is-your-furnace-blowing-cold-air","status":"publish","type":"post","link":"https:\/\/www.a1mechanical.com\/blog\/heating-service\/why-is-your-furnace-blowing-cold-air\/","title":{"rendered":"Why is Your Furnace Blowing Cold Air?"},"content":{"rendered":"\n
\"Furnace\"<\/a><\/figure>\n\n\n\n

When the temperature drops outside, the last thing you want to deal with is a gas furnace that doesn\u2019t work. We understand the frustration homeowners feel when they have to schedule furnace repairs, which is why we always strive to let homeowners know what they can do to prolong the lives of their furnaces.<\/p>\n\n\n\n

In this blog post, the Lansing furnace repair contractors at A-1 Mechanical will go over the reasons why your furnace is blowing cold air so you can keep your home comfortable year-round.<\/p>\n\n\n\n

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Is Your Thermostat Set to \u201cOn\u201d Instead of \u201cAuto\u201d?<\/h2>\n\n\n\n

If your furnace is blowing cold air, don\u2019t panic. The solution may be simpler than you think. Before calling a heating and cooling company, check to see that your thermostat is set to \u201cAUTO\u201d. This will be the first thing a furnace repair contractor checks.<\/p>\n\n\n\n

Your furnace is designed to kick on once the temperature inside your home drops below the programmed temperature setting. When the thermostat is programmed to \u201cAUTO\u201d, this means the furnace blower will only push air through the vents when the burners are on.<\/p>\n\n\n\n

If the thermostat is set to \u201cON\u201d, the furnace blower will constantly push air through the vents, regardless of whether it\u2019s heated or not. Changing this setting yourself is simple and can save you the cost of having a HVAC repair contractor come out to your home.<\/p>\n\n\n\n

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Is Your Furnace Overheating?<\/h2>\n\n\n\n

You\u2019ll know your furnace has overheated if you notice it blowing hot air, then cold air, before stopping completely. As a safety precaution, your furnace will automatically shut off the burners and continue running air to cool down the unit. Your furnace completely shuts off once it has reached a safe temperature.<\/p>\n\n\n\n

A common reason why furnaces overheat is dirty air filters, which block airflow and cause your furnace to work harder to produce the same amount of heated air. If you recognize the signs of an overheated furnace, call a furnace repair company as soon as possible. A dirty air filter is easy and inexpensive to replace compared to having to repair the heat exchanger.<\/p>\n\n\n\n

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Is Your Furnace Pilot Light Out?<\/h2>\n\n\n\n

The pilot light is responsible for igniting the gas in your furnace and heating air. However, if the pilot light is out, your furnace will only be able to blow cold air. Each furnace is a little bit different for how to light the pilot. Be sure to check with the manufacturer\u2019s instructions before attempting to light a gas furnace. If the pilot light refuses to stay lit, you\u2019ll need to call a furnace contractor to fix any issues with the thermocouple. While minor issues can be handled by experienced homeowners, you should always call a professional for any residential furnace repairs outside your comfort zone.<\/p>\n\n\n\n

Frequently Asked Questions<\/strong><\/h2>\n\n\n\n

Question: Why is my furnace blowing cold air?<\/strong>
<\/strong>Answer:<\/strong> Your furnace may blow cold air if the thermostat is set incorrectly, the system has overheated, or the pilot light has gone out. Checking these common causes can help determine whether the issue is simple to correct or requires professional furnace repair.<\/p>\n\n\n\n

Question: Should my furnace thermostat be set to AUTO or ON?<\/strong>
<\/strong>Answer:<\/strong> Setting the thermostat fan to AUTO allows the blower to run only when the furnace burners are producing heat. If the fan is set to ON, it can continue circulating unheated air between heating cycles, making the air from your vents feel cold.<\/p>\n\n\n\n

Question: Can a dirty air filter cause my furnace to blow cold air?<\/strong>
<\/strong>Answer:<\/strong> Yes, a dirty air filter can restrict airflow and make the furnace work harder, which may eventually cause the system to overheat. When this happens, the burners can shut off for safety while the blower continues running to help cool the furnace.<\/p>\n\n\n\n

Question: Why does my furnace blow hot air and then cold air?<\/strong>
<\/strong>Answer:<\/strong> A furnace that blows hot air followed by cold air may be overheating and activating its built-in safety controls. The burners shut down while the blower continues moving air through the system until the furnace reaches a safer operating temperature.<\/p>\n\n\n\n

Question: Can a pilot light cause a furnace to blow cold air?
Answer:<\/strong> Yes, an extinguished pilot light can prevent a gas furnace from igniting the fuel needed to produce heat. If the pilot light will not stay lit after following the manufacturer\u2019s instructions, a furnace technician may need to inspect the thermocouple or other components.<\/p>\n\n\n\n

The HVAC technicians at A-1 Mechanical want to make sure your HVAC system doesn\u2019t surprise you with sudden costly repairs. If your home could benefit from any of our furnace installation and replacement services or furnace repair services, please contact our Lansing heating and cooling contractors at (517) 272-8629.<\/p>\n","protected":false},"excerpt":{"rendered":"

When the temperature drops outside, the last thing you want to deal with is a gas furnace that doesn\u2019t work. We understand the frustration homeowners feel when they have to schedule furnace repairs, which is why we always strive to let homeowners know what they can do to prolong the lives of their furnaces. In […]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[88,76],"tags":[13,6,121],"_links":{"self":[{"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/posts\/4428"}],"collection":[{"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/comments?post=4428"}],"version-history":[{"count":3,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/posts\/4428\/revisions"}],"predecessor-version":[{"id":5073,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/posts\/4428\/revisions\/5073"}],"wp:attachment":[{"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/media?parent=4428"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/categories?post=4428"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.a1mechanical.com\/blog\/wp-json\/wp\/v2\/tags?post=4428"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}