If the car does get up to temperature as it should, there’s probably something else that has gone bad. Why is the Heater Not Working? When the ac is of the radiator hoses both become same heat after a while and the overflow reservoir starts boiling over and the fan do not kick in. The water pump works off of centrifugal motion and is ran by the engine so at higher RPM's it pumps more water. 1 Answer. 9 years ago. Archived. If a thermostat is stuck in the closed position, it will never allow coolant to circulate fully, so no heat for you. Many times, burning smell from car may come from the clutch problem. Recent Mercedes S Class and BMW Alpina B7s are among the cars I've driven with this feature, and wondered why. The AC button on the center counsel of my car does not light up but all other buttons on my center counsel light up and work fine. To diagnose why the air conditioning in your car isn't working, start by turning your car on and setting the AC to full blast. Reasons Why a Car Heater Stops Working . Why does my car shake when i have the AC/Heat on? Instead, you might have a failed thermostat, which opens and closes circuits in the cooling system as the engine heats up. my compressor in my 05 liberty comes on and off when the heat is on i dont know why, i thought it onley comes on when the aircondi is on can any one tell me if this is normal. Thankfully, you can just turn on the defroster and let your car do the work of clearing away that unwanted moisture for you. Press question mark to learn the rest of the keyboard shortcuts. Why does my car shake when i have the AC/Heat on? When the coolant cools, it goes back to your engine and the whole process starts over. 2008 Chevy Aveo This morning I moved my car to find a small puddle of water on the driveway. But the car's computer (PCM) should bring the idle speed back up. Car heater problems are also frequently associated with heater core difficulties: coolant may not be traveling through the heater core properly, the air from the blower motor is not reaching it or there’s a clog in the small tubing of the heater core. User account menu . Set it to turn on the AC or heat. World War II proved a major catalyst, because for the first time, military vehicles were able to provide comfort for troops fighting in cold weather. These causes below will show the specific reason why your car have burning rubber smell. It was clear and odourless so there is no coolant leak, coolant loss or any coolant smells coming from the vents or engine. Even if you have the heat / AC system turned off, the engine will still blow air through the system when it is operating. It then runs through piping to your cabin, where a mini radiator (or heater core) holds hot coolant. Posted by. Step 4 Remove the cover for the thermostat and unscrew the wire from the Y terminal (it should be marked). Clutch problem . Fins attached to the core tubes serve to increase surface area for heat transfer to air that is forced past them by a fan, thereby heating the passenger compartment. when i stop it blow cold air. Heater cores, in a nutshell, are cooling system parts that resemble compact radiators. The only reason why you may have insufficient levels of refrigerant is when you have a leak in the system. Why Does My Air Conditioning Run at Only One Speed? If your car has not been overheating or running hot, your water pump is not the culprit. The way to find out how to fix it, is to first find out why does it happen. This is considered normal, but if there is a LOT of heat, then there is something else amiss. Older cars with larger engines were burning more fuel, but they were warming up faster. It was hot even when turned to cold. There are many reasons your car's heater isn't working. No heat to feet or defrost. A heater core is a radiator-like device used in heating the cabin of a vehicle.Hot coolant from the vehicle's engine is passed through a winding tube of the core, a heat exchanger between coolant and cabin air. When you turn on the heat inside the car, a valve is opened so hot coolant can flow to the heater core (on some cars), or a door is opened to direct air through the already hot heater core. why does my compressor come on and off when the heat is on in my 05 liberty is this normal? Answer Save. A fan blows over your heater core and directs warm air into the cabin. They may or may not be the same. By Rick Popely. #1. I replaced water pump and radiator and coolant temp sensor. This is because there is no space for the refrigerant to escape and evaporate. Before going into greater detail on why the heater may not be working and how you can maintain the system, let’s talk about the heater in your car. When the AC clutch engages to run the compressor, it places an additional load on the engine. Different devices, such as the home refrigerator, home A/C system or your vehicle may use different types of refrigerants. Troubleshooting a car's air conditioner is an important part of knowing your car, and can be a real life-saver in the summer heat. A sticking valve may mean that that the air is constantly taking the "hot" path through the matrix rather than the cold path. If strange noises are coming from the AC, there could be an issue with the compressor and it may need to be fixed or replaced. Some modern cars not only take stuff out of the air but also put scent into it. A blast of arctic air is coming. I started the car and turned the heater on without the A/C and took a peek underneath to find quite a bit of water leaking from the bottom of the car. Hold the wire by the insulation and touch the bare end of the Y wire to the R terminal to bypass the thermostat. Before replacing Heater Control Unit, it would only blow hot air from front vents- With this replacement it will now change from cold to hot and the air flow pressure does change from the front vents when changing the setting dial but there is still no air at all to feet and defrost. Read on to see what causes a car heater to blow cold air. The heat shield that is mounted on your car is supposed to last as long as the car does. Your car’s defroster is tied into the air conditioning system. A lack of heat can be a symptom of a much larger problem. i dont get it. This allows the heater to come online before the engine gets up to full operating temperature. Clogged Radiator. It’s time to check that heating system to be sure you have no surprises. However, if there is a problem with the AC, even normal usage can cause it to overheat. This will save you time and money with a mechanic, and could make it possible for you to fix the problem yourself. Here’s Why Your Car Has No Heat. Did you know it’s part of the cooling system? Heating in cars works by air being drawn through a heater matrix - this is like a little radiator that gets hot with engine coolant. Trying to work out why your car heater isn't working and why the car heater is blowing cold air when it should be hot? In cars powered by an IC engine, the heating system draws heat from the engine's coolant. Hence, this heat gets blown through the AC vents in the passenger compartment. Radiator fluid runs through the engine and becomes hot. Each time a spark ignites the fuel in the engine, there’s a tiny explosion that generates a lot of heat. 2 years ago • News. I had a car that did this. 6 Answers. The AC and Heat knobs do not work either. How Does Your Car Heater Work? 2. Close. Due to the moisture that is produced by the engine, eventually a metal heat shield will begin to show signs of rust. 1 year ago. You could soon be facing failing parts or even a blown engine. log in sign up. alr538. On most cars, the heater core is a bypass system -- it draws fluid directly from the engine without waiting for it to pass through the thermostat. Lv 4. A brief initial loss of rpm as the AC comes on is normal. Maybe the fan is malfunctioning. Your hearer core is getting plugged up or your water pump is going bad. My 2013 Hyundai i10 has one fan and as far as I can see one coolant temp sensor. r/MechanicAdvice. Share CARS.COM — It’s hard to dispute that few things are as unpleasant as setting foot inside your car … It’s really quite ingenious. How a defroster works. In an airtight car AC system, there is no need to recharge or top up the refrigerant. 4. u/wholemilkmargot. January 17, 2016. So, you can recognize this quite easy. Walk to the AC/heating unit and listen for the motor to turn on. Air-conditioning (AC) is one of the many features of a car to make commuting comfortable and is used almost always irrespective if the weather hot, cold, raining or snowing. You realize that you really can’t go anywhere because your windshield is fogged up. By this time, heater cores were the norm, because gas heaters were too costly and risky, and simply using ambient heat from the engine wasn't potent enough. 4. The condenser fan (if it has a dedicated fan) or the radiator fan most always comes in (with AC on) when the compressor discharge pressure (or, alternatively, the liquid line one; look for where a sensor or a switch is located on the high pressure line) rises over an operative threshold. Posted by John Goreham. There are a few reasons why a car heater may be on the fritz—it depends on the nature of the problem. The first cold days are here and now your car has no heat. When I turn on the ac the fan works and keeps the car cool. my heat only works when my car is in motion . Press J to jump to the feed. Does your car idle rough when you turn on the air conditioning? Heater working but only blows out front vents. GM introduced car seat heaters in 1939 on select cars. When your air conditioner won’t work, put on your DIY hat, take a look at the system, and try to figure out what’s wrong. Favorite Answer. Relevance. There could even be a puddle of liquid under the front of the vehicle. Hello I am having problems getting my AC/Heat to work in my car. It happens whenever you shift gears and the smell is usually similar to that of a burning newspaper or the burning rubber smell from car. As with any other metal component, rust is one of the biggest enemies that the heat shield on a car will have. Your engine's cooling system builds up an enormous amount of pressure. If it doesn't, there could be something wrong with the thermostat. We run down the reasons why so you can feel warm and toasty again. With the coolant typically at close to 200 degrees, it can quickly deliver a significant amount of hot air to your feet or the foggy windshield. 1. Modern cars have smaller fuel-efficient engines that burn less fuel and, as a result, generate less heat. It does this by absorbing and releasing heat, ultimately leaving cool air behind. r/MechanicAdvice: This is more than a car repair forum! Perhaps your temperature gauge is running below normal. Be something wrong with the AC comes on is normal cars not take... Press question mark to learn the rest of the problem in my 05 liberty is this?. Clearing away that unwanted moisture for you it happen it ’ s a tiny explosion that a! The rest of the vehicle the fuel in the system 's coolant puddle of liquid under the front the... Full operating temperature i10 has one fan and as far as I can see one coolant temp.! 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