Why Won’t My Ride Get Warm?
Does your trusty ride seem to be taking, like, forever to heat up on cold days? Is it harder than usual to de-fog the windshield? Are you shivering aggressively through ever-greater portions of your wintertime commute? Pretty sure your ride just isn’t heating up like she used to?
Well, it may not be – and you’re probably not alone.
Below, we’ll look at a few reasons that your ride’s heater and defogger systems may be performing poorly, and a few mistakes you might be making that aren’t helping either.
You think it’s silly to use A/C at 20 below
Turn on your defogger, or set the climate control to Auto, if equipped, and sometimes, you see the air conditioner turn on, even in extreme cold. Stupid idea, turning on the A/C while you’re trying to warm up, right? Actually, no: your ride’s air conditioner cools air, but also dehumidifies it – which makes it a powerful tool when you need to de-fog your windows. Many cars automatically switch the A/C on to remove frost and fog-causing moisture from the cabin in extreme cold, and many owners turn it back off, not knowing any better. Leave the A/C on when it turns itself on in the winter, or turn it on manually when you’ve got frosty interior windows. You’ll have a clear outward view much faster than without it.
You’re cranking the heat too soon
When you turn on the heat in your ride, a variety of processes kick into place to transfer heat from the engine coolant into the cabin, warming those inside. Thing is, in extreme cold, cranking the heat the instant you start a cold engine can slow the rate at which that engine heats up, meaning it’ll likely take longer before the engine actually generates enough heat to get the cockpit nice and toasty. After all, turning on your ride’s heat effectively helps cool its engine. And if the engine is trying to heat up, while you’re cooling it down, it won’t heat up as quickly. It’s like walking up a “down” escalator.
Solution? In extreme cold, let your engine run a few moments with the heat off, or on a low setting, when you first start it up. Chances are, you’ll get warmer, more quickly, if you do.
Your heater core is clogged
The heater core of your ride is like a mini radiator through which two things pass. The first of these is hot engine coolant, and the second of these is the air pumped through the climate control system. The climate control fan pumps air past the hot heater core, transferring heat to the cabin of your ride. But sometimes, the trusty heater core can require attention, and in many cases, can become plugged up with age. If your vehicle just isn’t heating up the way it used to, many shops can perform a heater core flush, which removes deposits that may be affecting its performance. Go from a clogged heater core to a clean one, and your heating performance will improve – but talk to the technician of your choosing for help in deciding how to tackle your specific heater performance problems.
Your cabin air filter is clogged
Do you know what a cabin air filter is? If not, chances are, the one in your vehicle is clogged full of dust, bugs, dirt, leaves, and other debris. Many vehicles have a cabin air filter, through which all air used to heat (or chill) the cabin must pass. Over time, as filters do, this filter will clog up and require replacement.
Auto service technician John Kennard says that most shoppers he sees don’t know about the cabin air filter, and never change it.
“It’s funny how many people don’t read their owner’s manual, and a lot of these customers look at me like I have two heads when I ask them when they last replaced their cabin air filter,” he says. “If a customer has some problem with their heater or A/C, and they haven’t ever changed their cabin air filter? It’s badly clogged, and affecting system performance significantly, more often than not.”
A clogged cabin air filter is a leading cause of lousy heater and defogger performance in cold months. The clogged filter prevents proper air flow into the cabin, and can drastically reduce the performance of the air conditioner as it tries to suck moisture from the cabin. In extreme cases, a badly clogged cabin air filter can even cause the A/C system to turn itself off.
If you are running a years-old cabin air filter in your ride, changing it will likely make a huge improvement to the performance of your HVAC system.
Snow and ice are blocking your air intake
Another possible cause of poor heater performance is a blockage of the climate control air intake system. Typically, air is sucked into your ride’s cabin through a vent in the area between your windshield and hood, down in the vicinity where your windshield wipers park. If this vent is blocked by leafy tree debris from the fall, and then covered in frozen snow and ice, it’s not sucking up enough air, and heater system performance will suffer. Determine where this important air intake vent is located, and keep it clear.
