My 2013 Hyundai i10 has one fan and as far as I can see one coolant temp sensor. alr538. GM introduced car seat heaters in 1939 on select cars. It’s really quite ingenious. Answer Save. 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. Your engine's cooling system builds up an enormous amount of pressure. 4. How a defroster works. Perhaps your temperature gauge is running below normal. The AC and Heat knobs do not work either. Why does my car shake when i have the AC/Heat on? Heater cores, in a nutshell, are cooling system parts that resemble compact radiators. You could soon be facing failing parts or even a blown engine. Your hearer core is getting plugged up or your water pump is going bad. 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. i dont get it. Clutch problem . Posted by John Goreham. 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. 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. Press J to jump to the feed. Share CARS.COM — It’s hard to dispute that few things are as unpleasant as setting foot inside your car … 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. 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. But the car's computer (PCM) should bring the idle speed back up. Does your car idle rough when you turn on the air conditioning? If it doesn't, there could be something wrong with the thermostat. 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. 2. 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. A brief initial loss of rpm as the AC comes on is normal. I had a car that did this. 4. Each time a spark ignites the fuel in the engine, there’s a tiny explosion that generates a lot of heat. Posted by. 2 years ago • News. The way to find out how to fix it, is to first find out why does it happen. Press question mark to learn the rest of the keyboard shortcuts. By Rick Popely. Clogged Radiator. 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. Lv 4. The only reason why you may have insufficient levels of refrigerant is when you have a leak in the system. 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. Favorite Answer. It does this by absorbing and releasing heat, ultimately leaving cool air behind. 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? my heat only works when my car is in motion . Walk to the AC/heating unit and listen for the motor to turn on. A sticking valve may mean that that the air is constantly taking the "hot" path through the matrix rather than the cold path. Heater working but only blows out front vents. Modern cars have smaller fuel-efficient engines that burn less fuel and, as a result, generate less heat. 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. We run down the reasons why so you can feel warm and toasty again. Your car’s defroster is tied into the air conditioning system. when i stop it blow cold air. As with any other metal component, rust is one of the biggest enemies that the heat shield on a car will have. 6 Answers. The water pump works off of centrifugal motion and is ran by the engine so at higher RPM's it pumps more water. This allows the heater to come online before the engine gets up to full operating temperature. When the coolant cools, it goes back to your engine and the whole process starts over. 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. 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. 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. Did you know it’s part of the cooling system? u/wholemilkmargot. Heating in cars works by air being drawn through a heater matrix - this is like a little radiator that gets hot with engine coolant. In an airtight car AC system, there is no need to recharge or top up the refrigerant. How Does Your Car Heater Work? In cars powered by an IC engine, the heating system draws heat from the engine's coolant. There are many reasons your car's heater isn't working. It then runs through piping to your cabin, where a mini radiator (or heater core) holds hot coolant. I replaced water pump and radiator and coolant temp sensor. 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. A blast of arctic air is coming. Here’s Why Your Car Has No Heat. Even if you have the heat / AC system turned off, the engine will still blow air through the system when it is operating. They may or may not be the same. Hello I am having problems getting my AC/Heat to work in my car. #1. If the car does get up to temperature as it should, there’s probably something else that has gone bad. 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. It was hot even when turned to cold. Why does my car shake when i have the AC/Heat on? 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. This will save you time and money with a mechanic, and could make it possible for you to fix the problem yourself. This is considered normal, but if there is a LOT of heat, then there is something else amiss. User account menu . No heat to feet or defrost. A lack of heat can be a symptom of a much larger problem. There are a few reasons why a car heater may be on the fritz—it depends on the nature of the problem. Hold the wire by the insulation and touch the bare end of the Y wire to the R terminal to bypass the thermostat. Instead, you might have a failed thermostat, which opens and closes circuits in the cooling system as the engine heats up. Heat only works when my car shake when I have the AC/Heat on a. 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