Most times, a heater blows cold air because something’s preventing airflow or heat to escape from it. When this happens, the system blows cold air to prevent it from overheating. While many of the solutions are easy to handle, it’s important to fix the problem right away.
In this article, we’ll start by explaining why you should act quickly if your heater blows cold air. It’s unlikely you’ll be in danger. But, you do run the risk of badly damaging your system — even causing it to break down for good — if you don’t address the problem.
Then, we’ll walk you through four common causes. And, we’ll let you know how to handle each one. Some are simple enough for you to handle on your own. In other cases, you’ll need a professional.
If it’s more than you can fix on your own, call or email us here at Air Comfort Technologies for help in your South Central Pennsylvania home or business.
Why You Shouldn’t Ignore A Heater Blowing Cold Air
In many cases, you can make a quick, safe, and easy fix yourself when the heater is blowing cold air. But, you never want to ignore any HVAC problem because it will only get worse. And, if your heater switches to cooling when you want heat, it can cause excess wear and tear on the system.
The problem is those sudden, severe temperature swings inside the system. That fluctuation causes some of the components to stress, weaken, and eventually break. In some cases, as with a heat exchanger, a broken part can mean you need a whole new system.
So, follow our troubleshooting guide and keep your HVAC system running well for years to come.
Three Reasons Your Furnace Blows Cold Air (And What To Do About It)
Here are four common troubleshooting tips for when your furnace blows cold air. We’ll start with ones you can solve yourself and work up from there:
– The Thermostat Is Set Wrong
– The Air Filter Is Clogged
– Your System Is Too Big For The House
The Thermostat Is Set Wrong
If your thermostat is set to “Fan Only,” then you’ll get cool air when really you want heat.
This is a simple problem with a simple solution, and, it occurs more often than you may think.
Most thermostats have three settings: Heating, cooling, and fan only. With “Fan Only,” you’re running the blower motor but not the furnace or AC condenser. It’s only circulating the air throughout the house without adding any treatment to it.
And, in the winter, that air is cold. So, if you’re expecting heat but are on this setting, it can seem like the system is malfunctioning.
What To Do About It
Check your thermostat. Along with the temperature setting, you’ll have those three choices we outlined above. Change it to heating if you’re not on that setting already. The next time the system clicks on, you should start getting warm air.
As a side note: Be careful not to leave your system set to cooling when you go to turn on your furnace in the fall! You can damage your AC condenser by trying to run it when the temperature is lower than 60 degrees outside.
The Air Filter Is Clogged
The air filter is the screen that catches dust, dirt, and other small particles before they get into your furnace and cause problems. It sits at the point where the ductwork meets the unit. And, when it gets full, it clogs and causes issues itself.
All that dust and dirt coming through the ducts collects on that screen. But, the filter still needs to let air pass through it. When it’s clogged, not even the air can get through. At that point, you’ll notice your system “short-cycling.”
That’s when it turns on for a moment and then turns back off. In this case, it happens because the system generates heat, but there’s no air flowing through to move that warmth out of the system.
That excess warmth can cause the system to overheat. As a failsafe, the furnace shuts off and switches to cooling for a moment to cool things down. It can cause significant problems down the line.
What To Do About It
Ideally, you should change your air filter every month that you’re using your heater or central air. That way, it’s always letting the air through. If yours has been sitting for a while, start by swapping it out with a new one.
If the screen is grey when you remove it, it accumulated more dirt and dust than it should have. So, this may have solved the problem. Put in a new one and see if you get warm air consistently after that.
Your System Is Too Big For The House
If your system has always short-cycled, it may be too powerful for your house. When it comes to HVAC, bigger is not better. An oversized system won’t work correctly. And, it’s a more common problem than it should be.
Here’s the problem on the heating side: A furnace that’s too powerful blasts too much hot air at once into the house. That causes a quick temperature rise, so the thermostat shuts off the system because it’s reached the call settings.
But, the heaters need to pump in warmth slow and steady for at least 15 minutes. When it only stays on for a minute or two, what little heat doesn’t last. Meanwhile, with nowhere to go, that excess heat backs up into the system. When that happens, it switches to cold air, so nothing overheats.
What To Do About It
Start with your air filter. With any luck, a lack of airflow is what’s causing the short-cycling and cool air. But, if it keeps happening after that, call a professional. They’ll be able to tell you if your system is too powerful. That’s based on the layout and size of your home. And, how that stacks up against the model you have.
Furnace Repair In Hanover, PA
If your heater is blowing cold air in the winter, or if you’re noticing other problems during the winter with your HVAC system, contact us Air Comfort Technologies for furnace repair or service. We have an excellent reputation for helping homeowners and businesses in Hanover, York, and other South Central Pennsylvania towns. Click below or call.