Why is my heating system blowing cold air with the heat still on?

February 1, 2016 

Your furnace is on but the blowing air is cold. 

You can start by looking at several common trouble spots yourself before calling for repairs.

Make sure the thermostat is set to auto instead of the on position. On will cause the blower to operate non-stop, even without the heating element functioning in Smithtown.

The result will be you should feel the air blowing from the vents with the air coming out close to room temperature or colder.

Often overlooked is a simple fix. Some customers are unaware that furnace filters need to be changed regularly. When a filter is dirty and clogged, the furnace gets overheated, like a restricted radiator in your car can overheat your engine. When your furnace overheats there is a safety mechanism that causes your furnace to shut off, rather than potentially melting or causing a fire.  Moral is to change your filter regularly.

Other reasons your system may not be operating properly

There are times when it is safer to call for service than risk significant damage to your heating equipment. If you have checked the above items and cold air is still blowing through the vents, you are going to want a trusted technician to diagnose your issue.

Make sure you have carbon monoxide detectors near your heating system. If you have an older furnace with a standing pilot, the pilot light may be out but gas still flowing. If you try and light the pilot, you can envision an explosion. Safety first, call the professionals.

There may be a situation where you are not getting enough gas to start the furnace.

With newer 90+ AFUE high efficiency furnaces the condensate lines may be blocked or need clearing. When the condensate line gets blocked, it can activate a safety switch preventing ignition of the furnace burner. 

***Note: Higher efficiency furnaces can qualify for significant rebates from your utility company.*** 

When you have these issues on Long Island we can diagnose and solve your furnace issues.

Our management team at True Mechanical has well over 100 years’ experience in all phases of heating and cooling. 

We offer affordable service,calls and service contracts. We offer no charge quotes on system replacements. True Mechanical is 40 years in business and with over 100,000 installations on Long Island. Visit our website at www.truemech.com. 631-563-1298.

We ask for your input and comments. If there is an industry subject you wish to know more about, please let us know.

About the Author. Brian Nagle started in the HVAC industry in 1996 on Long Island and has been with True Mechanical since 2011. Additionally, he has over 20 years experience in finance and aviation management. 

Brian can be contacted at the office number above or by email at brian@truemech.com.

True Mechanical Corp, Bohemia, NY  www.truemech.com 

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