Is Your Furnace Blowing Cold Air?
It’s cold outside, and you’re looking forward to warming up in your heated home. However, once you get inside, you notice that your house isn’t warm at all. Then, you head over to your vents and quickly realize that cold air’s being blown into your home instead of hot. “Why is it blowing cold air?” you ask no one in particular, exasperated.
There are several potential reasons why this may be the case, and we’ll discuss a number of them to help you ease your worries.
Incorrectly Set or Broken Thermostat
Did you or someone else in your home incorrectly set your thermostat? Perhaps it’s been set for summer conditions. Also, ensure that its setting is “Auto,” not “On.” That way it won’t blow air when it’s not supposed to. Additionally, check if its batteries are charged and that the thermostat isn’t broken.
Note that your fan limit switch may be the cause of your thermostat no longer working. This measures the furnace’s air temperature, and its intent is to not blow air if there’s no warm air to be blown.
Furnace Hasn’t Warmed Up Yet
Don’t worry if you’re turning on your furnace for the first time this winter and cold air’s coming out of it. You may just need to wait for your furnace to warm up.
Also keep in mind that some furnaces may experience a warming-up period much more often than that. Regardless, it should work itself out in a few minutes.
Furnace Has Overheated
If your furnace has overheated, that could be why cold air’s being blown out of your vents. This is especially likely if the air was warm and then gradually became cool until nothing at all ended up being blown out.
Clogged or dirty filters are usually the cause of an overheated furnace. Fortunately, if this is what happened, a relatively easy solution will usually follow: Clean or, if necessary, replace your filters.
Another potential cause of an overheated furnace are clogged coils. Cleaning and replacing those can be a DIY project as well, but they normally require a lot more care than is the case for filters.
Damaged Air Ducts
If you have holey or otherwise damaged air ducts, that could be the culprit. That’s because leaks here are allowing much of the hot air to escape before it reaches your vents and cold air to be sucked in. If this is the issue and the leaks or cracks are minor enough, you may be able to fix this yourself. Otherwise, it’s best to call a professional.
Blocked Air Vents
You need the air flow from your heater to not be impeded en route to and through your vents. If any of your vents are blocked or simply closed, that could be why you’re feeling cold air come out, and you should unblock them if doing so is possible.
Cracked Heat Exchanger
The heat exchanger is what absorbs the heat that your furnace is creating before ultimately passing that warm air on to your home. If it’s cracked, that could cause a leak of combustion gases, such as carbon monoxide, which can create a dangerous situation. This can also lead to an inability to heat the air or, in some cases, the system turning off the heating system for safety reasons and you feeling the blower fan blowing unheated air into your home.
Flame Sensor’s Dirty
If your flame sensor’s dirty or damaged, it may not accurately sense if your burner flame’s on. That could result in unheated air being sent around your house, such as could be the case if your blower fan’s running while there’s no flame and, as a result, no heated air. If you want to clean this yourself, you can, but take great care when doing so. Also make sure to completely turn off the furnace before you do.
Gas-Supply Issues
If there are issues getting the gas to your furnace in order to heat it, whether that’s the result of a damaged gas line or otherwise, you could then have your fan working hard despite no heated air being accessible.
Pilot Light’s Out
Those who are using older furnaces should keep an eye on their pilot light. It should always be lit, so if you see that it isn’t, this is likely the cause of your cold home. You can, after turning off your thermostat, relight it.
However, if you then see it go out again right away, it’s likely that you’re dealing with gas-supply issues and should reach out to a professional to investigate the situation further.
Worn-Out Parts
If it’s been decades since your heating system was installed with at least some of its parts not having been replaced yet, them being worn-out could be what’s causing cold air to be blown out of your heating vents. That’s because old parts can result in leaks and other issues, including damage caused by them to other elements of your heating system.
In this case, replace those parts with newer, more effective ones.
Careless Installation or Maintenance
If someone installed, maintained or repaired one or more parts of your heating system but did it carelessly and ineffectively, that could be the general cause that’s resulted in one of the aforementioned issues to occur.
Consult Professional Assistance
If you’d like to procure professional assistance with your issue or simply need to because the job is too time-consuming, complicated or dangerous to handle, reach out to One Hour Air Conditioning & Heating. We regularly help those in Birmingham, AL, who are struggling with either a gas or electric heating system that’s cooling them down instead and would be glad to do the same with you.
And you don’t have to worry about setting aside a large chunk of your day when you arrange a time for us to fix your heating system since we’re on time or you don’t pay a dime.
