A few things can make your heater blow cold air:
- There’s something wrong with your thermostat.
- Your heater is too big for the house
- Something’s blocking the vents
- There’s a leak in the ductwork
- You have a problem with the ignition or supply
You can check for most of these yourself. And, you can take care of a few of these as well. For the bigger items, of course, you’ll want to call in a professional.
Here at Bovio, we’ve got decades of experience locating heating problems and fixing them right the first time. You can see by our online reviews that we’ve got a long list of happy customers.
And, now’s the time to get this problem checked out. As you’ve certainly noticed, winter has finally arrived.
South Jersey gets its fair share of snow and freezing temps. From December through March, houses in Washington Township, Salem County and other places want nothing but heat in their homes.
So, if you suddenly get what feels like AC coming through your ducts, you know something’s wrong. Here are some items to troubleshoot.
A broken thermostat can make your heater blow cold air
First off, make sure it’s on “fan,” “on,” or “auto.” If there’s a cool setting, and it’s set to that, there’s your problem. Next, check the batteries. If they are low, they can mess with the device.
Now, this one sounds obvious, but there’s a little more to it: Turn up the heat if your home’s too cold.
It’s possible you had it set lower than the actual temperature in your home. If so, the system is actually trying to cool the place. But, at this point, you’ll also want to check the temperature near the device.
If it’s not as warm as the setting, but you’re getting cold air, there’s a problem. You might need a new one. Or, if the area is warm, then maybe you’re dealing with uneven air distribution.
In other words, what’s happening is that the area near the thermostat is plenty warm. So much, in fact, that the heater is trying to cool it back down. But, other parts of the house are chilly because they never got as warm as that area.
If that’s the case, try moving the thermostat if you can. If it’s too close to a vent, it may be getting more heat than other spots.
A vent is blocked
A heater blowing cold air could be a sign of a much bigger problem. We’ll get into that in a moment. But, the good news is, the reason it’s happening could be a really easy fix. That’s if a vent is blocked.
Here’s the deal: if the heat coming from your heater has nowhere to go, it backs up. When that happens, it can cause a problem.
These units are designed to send all that hot air out. If the heat stays inside it too long, it can damage the components.
To prevent this from happening, the heater switches to cooling. It prevents the unit from overheating. But, it cools off your house as well.
So, the first thing you want to check is if anything is blocking your vents. If something’s in front of the vent, like a couch, shelf, or bed, the heat can’t circulate.
Make sure each vent has at least a few feet of open space around it. This way, you’re sure the air can flow properly. A bonus: You’ll improve the airflow throughout your house. And, you’ll probably spend a little less money on heating the place.
Your heater is too big
Now, here’s the bad news. The easy fix is if the unit blows cold air because the vents are blocked. The much harder fix comes if the heater is too big for your home.
We run into this problem from time to time. It could be that someone didn’t measure your home accurately when they picked out a unit. Or, a previous homeowner went with a “bigger is better” mentality.
Whatever the case, you’re running into a similar problem as you did with the blocked vents. The unit is blowing way too much warm air at once. Your home doesn’t need that much heat. As a result, it has no place to go. And, again, it backs up into the system.
But, this time, there’s no easy fix. And, if it keeps happening, you’re looking at a furnace replacement.
All that switching from hot and cold stresses the metal parts. Eventually, you’ll end up with a cracked heat exchanger. That’s when a crucial part of the unit breaks.
Now, your heater is down for the count. It can leak carbon monoxide into your home, and it’s virtually impossible to fix.
If you realize early on that your heater is oversized, you at least have some options. You can look into replacing it. Or, you can modify your ductwork so that some of that heat gets diverted.
Unfortunately, neither of these options are easy on the wallet. But, catching on before there’s an emergency means you can take your time and find the best option.
There’s a leak in the ductwork
Ok, let’s back off the ledge a little bit. Sometimes, the problem is simply a leak in your ductwork somewhere. This is common in homes where there’s ductwork in the attic. It’s a hassle, but it’s at least fixable.
If the ductwork is not sealed, then outside air gets in. If it’s freezing out, and the ducts are in the attic, then the air getting in is cold. That’s what ends up circulating through the house.
If that happens, it’s at least not the heater giving you the chills. It’s cold air leaking into the system. You’ll still need to call someone to find the leak and fix it. But, it’s not nearly as dire as having to replace a whole system or renovate your ducts.
The heater may have an ignition or supply problem
Okay, one more possibility. This one has to do with the heater again. Your unit may be pushing the air just fine. The problem is, nothing is warming it. Hence, a cold front circulating through the house.
The cause could be an ignition problem. The pilot light on your heater is a crucial part of the process. It’s what makes the gas or oil to combust and create heat.
Usually, the system shuts off if the pilot light isn’t on. But, if nothing trips any sensors, the unit keeps pushing air. But, no combustion means no heat. Just cold air flowing through the system.
A supply problem is similar. That’s especially so when you’re cooking with gas, so to speak. If the gas supply is weak or blocked, there’s nothing there to heat up the air. Even if the pilot light is on, nothing is there to combust.
This could be a clog somewhere, or something broke along the line. Either way, you’ll want to call someone to check it out.
Does your heater blow cold air? Contact us at (856) 272-7000, or email us at firstname.lastname@example.org, and we’ll find out why and get your home comfortable, and all set for winter again.