When most people think about temperature control inside their vehicle, they usually consider them to be two separate systems. Heating is used in the winter, cooling is used in the summer, with the most important part of the process being comfort.
Imagine arriving at your destination if you’ve driven across town in one-hundred degree heat and no air conditioning. It would be a miserable experience. Equally so as the temperatures creep towards zero, without a heater warming the interior cabin.
What makes both possible is the ventilation system that connects all the parts together. Yes, you need a heater and an air conditioner. But without the ventilation system providing a way for cooled or warmed air to move, you would be left to control temperatures by raising and lowering your windows.
So, how does your car’s heating and cooling system work?
Let’s talk about how your heater and air conditioner are related.
How a car’s heater and air conditioning works
Your car’s heater is a smaller version of the cooling system. Coolant circulates through a small radiator, often called a heater core. A fan is used at the front of the heater core to blow the cold air from outside over the fins. As this air moves through the heater core, it heats and becomes the warm air that is pumped inside the cabin through the heater vents.
The cooling system consists of a compressor, condenser, and evaporator. Refrigerant is compressed in the compressor, which turns into a hot gas. It moves to the condenser where it is cooled to a liquid state. It continues to move through the system, returning to a low-pressure gas as it rapidly cools in the evaporator. A fan blows over the evaporator during this process, cooling the air that blows through the vents inside the cabin of your vehicle.
Sounds easy enough, right? It’s easy to see how they are both connected. But they intertwine even more.
As the engine runs and causes friction and combustion, heat builds. Most of this is expelled through the exhaust system, but the remaining heat must be handled in some way. Coolant and water mix within the engine block and radiator to release the heat into the atmosphere. On cold days, that heat travels inside your cabin for warmth. But on warm days, your engine could overheat if something disrupts this process. That means your heating system is responsible for keeping your engine functioning properly all year long.
Likewise, on cold winter mornings you might wake to a layer of frost spread across your windshield. It’s not just your car’s heating system that warms it up, it’s the cooling system too. Multiple components all work together to pull humidity out of the air, helping to defrost your windows so you can see to drive. If you notice defogging issues, it may be time to recharge your air conditioning system, or check for leaks or damage.
What are the common problems with a vehicle’s heating and cooling system?
Have you ever heard of a vehicle needing to recharge the air conditioning system? That means ensuring the refrigerant is at proper levels to do its job well.
From time to time, refrigerants can wear down or leak. If this is the case, the equipment should be repaired before refilling to ensure maximum efficiency. It can be difficult to tell as some leaks are tiny at best. But you can watch for puddles forming that are either green or orange. Healthy coolant will be green (ethylene glycol) or orange (Dexcool). If it puddles as more of a rusty color, that means the rust inhibitor in the coolant is no longer doing its job, so rust and scale are building up. Changing it out will breathe new life back into your heating and cooling system.
Topping off the coolant may seem like a quick and easy thing to do. You can buy coolant at your local auto parts store. But the bigger question is: why was it leaking in the first place? The way the system is built, it should never leak coolant. That means somewhere there is a compromise to the system. It could be a cracked hose. It might be a radiator cap gone bad. It could be a damaged water pipe. But if you don’t get to the root of the problem and fix it, you’ll continue to have trouble even after filling up the coolant.
Depending on how old your vehicle is could be a problem too. The EPA phased out the use of R-12 coolant in all refrigeration systems, replacing it with R-134. R-12 has been determined to cause ozone depletion, impacting the ozone layer. So it’s been phased out over time with one safer for the environment. If you still drive a vehicle that uses R-12, you may need to retrofit the system to handle the newer R-134 coolant. Seales, hoses, even the compressor might need to be swapped for a newer model.
Corrosion will also cause the core to leak. Over time, it may leak steam into the interior cabin and fog up your windows. You may also detect a leak by a sweet smell coming through your vents when the system is in operation.
Prevention methods
In most cases, your car’s heating and cooling system won’t create a lot of problems. If you pay attention to your car, running standard performance checks every time you drive, you’ll notice a problem long before it grows into something bigger. If you notice a problem with heating or cooling, hear a strange noise, or smell something unusual, don’t ignore it. Once may be a fluke, but if it happens multiple times, bring your car in for an inspection.
With winter coming, it’s especially important to ensure your heating system is working at its best. Have you noticed problems with your air conditioning this summer? Is your car not as cold as it once was? Schedule a maintenance visit today to ensure your heating and cooling system are fully operational.
It will ensure you have a stress-free driving experience every time you head out the door.
Imagine a sludgy, sticky, dark goo slowly flowing inside your car’s internal workings. As the refrigerant in your car’s air conditioning system breaks down, it slowly moves inside the compressor.
You push a few buttons or turn some knobs, and voila, you have warm air blowing on your feet or cool air chilling your face. How does it all happen? Well, it’s all thanks to the air blend box. This box lives behind your dash and serves up just the right air temperature right where you want it.
Your serpentine belt is a long belt that’s driven by your engine. It winds around several accessories that power important automotive systems. Let’s go over them.
Question: Why isn’t my air conditioner blowing cold air?
Last week I was out running errands and my temperature warning light came on – total panic! I pulled over and my car was overheating. After I waited for it to cool down, I went right into my Denver service center to have them take a look. My service adviser at Express Car Care told me my water pump was leaking and needed to be replaced. He said water pumps just wear out and that they need to be replaced, because they have the important task of pumping the coolant that cools the engine while it’s running.
Let’s talk about air conditioning service and repair issues today. Most of us in Denver don’t give our air conditioning a second thought – just as long as it’s making cold air. But it’s a complex and expensive system that we should think more about before it starts blowing out hot air.
Express Car Care Question: I was driving down the freeway in Denver and smoke started coming out of my car. I pulled over and called my husband. I had to be towed to my mechanic. He said my car had overheated. What can I do to prevent this from happening in the future?
Let’s talk water pumps for vehicles here in Denver. The engine in your vehicle is cooled by coolant/antifreeze mixed with water. This mixture circulates around the engine, absorbing some of the heat. The coolant then flows through the radiator where air cools it down for the return trip back through the engine. Your vehicle’s water pump is what drives this process.