Why Are My Vents Not Blowing Hot Air?


Troubleshooting steps for furnace blowing cold air


The middle of a cold Manhattan winter is a bad time for a furnace to break down. The coldest days of the season are the busiest for our repair technicians at Standard Plumbing, Heating & Air Conditioning.

Top furnace problems during cold weatherWaiting in a cold home until a technician can arrive is something you want to avoid. With this article on one of the biggest furnace issues that can happen in cold weather, you will have some troubleshooting steps to get the heater back on yourself.


One of the most distressing problems a homeowner can experience is when your vents are not blowing hot air. It may seem like your air conditioner is running.

While you may be worried your furnace has died, that probably isn’t the case. When a furnace appears to be blowing cold air, it’s a problem that can usually be fixed.

What to do first when your furnace is blowing cold air

Do not immediately call for a repair. While you may need a professional to fix your problem, you can eliminate some minor issues that may be causing the cool air first.

Standard Plumbing, Heating & Air Conditioning in Manhattan is here whenever you need a professional heating technician to service your furnace. Just call us at (785) 776-5012, or you can schedule service online. But before you do, we want to arm you with troubleshooting steps that could save you time and money by avoiding paying for a service repair.

Furnace Blows Cold: 4 Troubleshooting Steps

Here are the four basic steps a homeowner can try before calling a professional HVAC repair technician. You don’t need a lot of experience in home repair to tackle some of the most common reasons why a furnace can stop working. Most of these steps can be done easily and with little or no money.

Run through these questions. If the answer is yes to any of them (or even several of them), then you have the opportunity to fix the root of the problem quickly yourself.


The 4 steps to fixing vents not blowing hot air


Thermostat set incorrectly to OFF causes furnace blowing cold airMake sure that your thermostat is set for a temperature higher than the current temperature in your home. It is possible someone else in the home lowered the setting without you being aware.

You also want to make sure it is set to HEAT and not COOL or OFF.

While that may put a kid in timeout or a spouse in hot water, this is the easiest problem to fix, at least technically.

If this is the problem, simply setting the temperature up several degrees than it is now should pretty quickly cause your furnace to blow warm air again.



While you’re checking the thermostat, make sure you see what the FAN setting is. If it is set to ON, that could make it feel like cold air is coming up through your vents.

If the air in your home is already at the set temperature, the furnace will not be heating. Yet air will still be pushed out of your vents. Compared to the existing temperature, that air will probably feel cold, even air-conditioned.

Make sure your fan is set to AUTO. That will cause the blower fan to run only when the furnace is working to heat your home.



Dirty air filter can cause my vents not blowing hot airHaving a clean air filter is vital for your home’s entire HVAC system. It can even make a furnace start to blow cold air.

A dirty furnace filter can block a sufficient amount of air from flowing through the ductwork. This can cause the heat exchanger to overheat, possibly creating dangerous problems like a cracked heat exchanger with a carbon monoxide leak. A furnace may shut off its burners as a safety precaution if this happens.

Change a dirty filter, even if it’s ahead of schedule for your regular changing. It may need to be changed more frequently than you realize.



If you have a gas furnace with a pilot light, you may find that it is not lit. Check where your burners are to make sure a flame is still burning.

If you need help, check this article for how to relight your furnace’s pilot light.


HOMEOWNER DIY vs HVAC Professional Repair

Standard Plumbing Heating & Air Conditioning has 24/7 emergency AC repair service in Manhattan, KSWhile those are the easy steps for homeowners to try to fix the problem themselves, none may end up solving your problem. There are various other (and more complicated) issues that can cause a furnace to stop blowing hot air.

If you need a professional to fix the problem, call Standard Plumbing, Heating & Air Conditioning at (785) 776-5012. We are available for 24/7 emergency furnace repair Manhattan, Wamego, Junction City and surrounding Kansas towns.

We can repair and service any type or model of furnace or heating system. We have hundreds of positive customer reviews and are the HVAC team trusted across the Manhattan, KS area.


Standard Plumbing Heating & Air AC repair van in front of Manhattan shop