Very cold air coming out of heat vents

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Happy New Year All. Recently bought a house In Pa. It’s winter so put the thermostat on 72 and waited for heat. Why is it that before the hot air come out of the vents, very cold air comes out? If we are sitting by the vents, we have to move because it gets so cold. Is there something wrong? Thank you for you answers.

  6 answers
  • Molly Anmar Molly Anmar on Jan 01, 2018
    Inconsistent temperatures coming from your vents signal that your ductwork is likely to blame. A certified heating technician will be able to diagnose your problem. If your ducts are properly sealed, cold wintry air could be creeping in from outside and cooling down your home while making your furnace work harder than ever.

    Once cold air has seeped into your ductwork, it must blow out of the duct registers before the furnace's warm air can—thus it feels like air conditioned air is ventilated through your home despite the thermostat being set to heat at 72-degrees.

  • Cindy Hagemann Cindy Hagemann on Jan 01, 2018
    You should get your unit serviced, if you have not done it before.

  • Gale Allen Jenness Gale Allen Jenness on Jan 01, 2018
    Not too unusual really, fan is kicking on before the furnace gets hot. You may be able to have that adjusted by a professional furnace repairman? It’s normal for the fan to run for several minutes after the furnace shuts off to help the furnace cool off! So one way or another you’ll probably still feel some cold air!

  • Gracie Gracie on Jan 01, 2018
    Because there is air in the system that has cooled since the last time the fan was on. As long as it heats up quickly, I think it's normal.

  • William William on Jan 01, 2018
    There is a control in the furnace that needs adjustment or replacement. That control monitors the heat in the furnace when it starts and turns the fan on when a set temperature is reached. It's called a fan and limit control. You need a heating professional to service the furnace.

  • Sandra Sandra on Jan 01, 2018
    I have the same question. It always does that so I thought it was normal.