Is it possible to switch on air conditioner in a car in winter?
So, is it possible to switch on air conditioner in a car in winter, when there are frosts outside? This question is asked by the drivers, who have heard an advice that it is necessary to periodically start this system to prolong its service life. The correct answer is that not only you can, but you should. But there are nuances.
For example, an air conditioner in a frosty weather can simply not start. And then the car owner has a number of other issues related to the work of the air conditioner system in winter. All details are in our article.
Why do you switch on air conditioner in a car in winter?
Any expert in auto conditioners will tell you – it is necessary to turn on air conditioner in a car in winter. And manuals of different car models’ users will confirm it. But why do it?
Scheme of work of air conditioning system in a car
The matter is that the system of air conditioning uses a special compressor oil. It is necessary to lubricate the compressor parts and all rubber seals of the system. If it were absent, the rubbing details in the compressor would simply become jammed then. However the oil itself does not circulate inside the system by itself; it is dissolved in freon, which is its carrier.
As a result, if you do not switch on a conditioner for a long time (for example, several months in a row, from autumn till the very summer), the first time, when you start it after a break, the compressor will work “without air”. Such a regime can lead to breakage or just to reduce significantly its resource. And the longer the system has been idle, the longer it takes for the oil to lubricate all the elements of the system again. The more the compressor is “killed”.
Working without lubrication, the compressor parts wear down and metal dust settles in the system. It’s almost impossible to flush and clean it out – it stays inside forever and will slowly kill even a new compressor.
And looking at its cost, no one would want to change this part (for Priora – 9,000 rubles, for Lacetti – 11,000 rubles, Ford Focus 3 – 12,000 rubles). Therefore lubrication of the system is the main reason why it is necessary to switch on air conditioner in a car in winter. Only the use of a car air conditioner in winter should be correct, otherwise you won’t be able to switch it on in summer.
But except for deterioration of the compressor itself, without greasing, rubber seals also suffer. And if they dry out, freon will start to flow out and evaporate. It is not as expensive as replacing the compressor, but it is also a few thousand rubles. And the cost is not even recouped, because if you do not find and fix the cause of the leak, freon will come out of the system again and the money will be literally thrown away.
In some articles it is possible to find the information that it is not necessary to switch conditioner on modern automobiles, because their compressor does not have an electromagnetic clutch, which gets stuck and which needs greasing. But these facts are not connected with each other – absence of a clutch, which is outside of a compressor, does not cancel necessity of lubrication of rubbing details inside of a compressor.
Confusion in a question “is it possible to switch on air conditioner in a car in winter” is caused by some factors.
- In the manuals, they do not write anything about the fact that it is necessary to start air conditioner at the positive temperature – nobody has found the answer, why it is not specified.
- Compressors of the majority of the cars, made after 2000, rotate all the year round and are called all-weather. The compressor’s work for pressure rise and clutch and pulley closing takes place inside the construction – so it is difficult to determine that it is really “running” and it makes it difficult to understand “if the air conditioner is on in winter”.
- Even if the compressor is switched off, the lamp AC lights up in a salon – we shall try to understand it separately.
How often should one switch on air conditioner in winter?
There is no uniform recommendation. The average value is once in 7-10 days for 10-15 minutes. It is better to search this information in the manual of concrete automobile. In general, it is the only reliable source of information, for which a carmaker is responsible with his head and risks possible suits. Even if you doubt whether it is possible to switch on air conditioner in a car in winter, look what the manufacturer has written. When it says “switch on”, then switch it on and do not be afraid of what will happen if to switch on air conditioner in a car in winter. If there is no such information – the final choice is yours. However, remember all those arguments, which have been given above.
Why there can be doubts at all, as the system needs greasing? As a matter of fact the conditioner does not start in a frost! Yes, even if the light of A/C is on on the panel. It needs certain conditions to start it.
Why does not the conditioner start in winter?
The air conditioning system of all automobiles, regardless of age and construction, does not turn on at low temperatures. Every automobile manufacturer has its own settings at what temperature conditioner does not work in a car, but the majority stays within the general range from -5°С to +5°С. Here is the data collected by journalists of the publication “Za Rulem” from automakers in Russia in 2019.
| Car brand | Minimum compressor operating temperature |
|---|---|
| BMW | +1 °C |
| Haval | -5 °C |
| Kia | +2 °C |
| MPSA (Mitsubishi-Peugeot-Citroen) | +5 °C |
| Nissan | -5. -2 °C |
| Porsche | +2. +3 °C |
| Renault | +4. +5 °C |
| Skoda | +2 °C |
| Subaru | 0 °C |
| Volkswagen | +2. +5 °C |
What does it mean? There is a freon pressure sensor in the design of the system that prevents a high pressure emergency in the first place. Roughly speaking, it makes sure the compressor doesn’t “over-pump”. But it also has a minimum pressure level, below which it considers that there is no freon in the system at all and also prevents the compressor from switching on.
At this point elementary physics works – the lower is temperature overboard, the lower is pressure in the system. At some moment (it is individual for each motorcar manufacturer) the sensor disconnects a possibility to switch on a conditioner. It is a safety mechanism, which protects the compressor from work in conditions of low pressure.
Why can a conditioner be switched on in some time after starting the engine and reaching the working temperature? No automobile manufacturer does not inform on settings of work of its systems of conditioning and a climate – control. But it is logical to assume that the compressor heats up in the under-hood of the car to the minimum required level and the pressure sensor allows the start.
But even in such situation, conditioner can switch off quickly, literally in 10 seconds after switching on. This is where the evaporator temperature sensor comes in – if it detects the risk of part icing due to low temperature around, the system will switch off again.
How to turn on the air conditioner in winter in a car
So, should you turn on your car’s air conditioner in the winter if it won’t start anyway? Yes, it is necessary to switch on it in order to expel oil, and to do this, there are the following variants:
- to warm up the car well, turn on when the torpedo in the interior is already warm;
- To switch on in any warm room: heated garage, warm box, closed parking lot, car wash (by the way, many car owners recommend just a car wash).
In such case you will exactly be able to switch on automobile conditioner in winter and even to control its work. It is easy to understand on old compressors with electromagnetic clutch, because a “click” occurs when switching on – it is a clutch gets engaged with a pulley. In modern systems of climate-control it is possible to understand that conditioner is functioning only in a warm box, after some time by checking air from air ducts or by watching revolutions by tachometer – they should increase.
How conditioner helps with weeping
Struggle against weeping.
One more reason why to turn on air conditioner in a car in winter is the struggle against window weeping. Any driver knows – if in a cold season the glasses begin to sweat, it is necessary to switch on air conditioner and heater simultaneously, to direct a stream of air on a windshield and the problem will be quickly eliminated. Moreover, in modern automobiles with systems of climate-control, if you switch air streams to a windshield manually, the conditioner will switch on forcedly. More precisely, the button AC will light up. The air is dehumidified and fogging is removed.
In spring and autumn, or more precisely at temperatures from 0 to +5°C, when you switch on the air conditioner, it starts and supplies cooled humid air to the evaporator. There the moisture condenses, the air is dehumidified and fed to the heater radiator. As a result, warm, dry air enters the cabin and helps warm the glass, absorbs moisture and eliminates fogging.
But in winter it is not so unambiguous. The problem is that if you dig into the physics of the process, the dehumidification of air at the evaporator of air conditioner is possible only at positive temperature.
Scheme of work of the system when dehumidifying glasses using air conditioner in winter
In frost, the moisture on evaporator cannot condense, because outside air gets on it and it simply will turn into ice. At this point, many drivers will say “in winter I turn air on windshield, turn on heating and A/C (or it switches on by itself) and sweating as if by magic”. One more widespread situation – in winter in a traffic jam the recirculation of cabin air is switched on not to breathe the exhaust gases in the outside air, and the windows mist up at once. Turning on the air conditioner helps to eliminate this unpleasant effect.
How the air conditioner works in summer and winter.
This is true and it can be explained as follows. In recirculation mode, when air conditioner is switched off, humid outside air is not dehumidified at evaporator, but is heated inside, where it is condensed again. When the heater heats air in the cabin up to plus temperatures, the usual process of boiling starts in air conditioner evaporator. At that, the heated saloon air actively absorbs moisture, which it leaves on the air conditioner evaporator. These processes are described in details in the video.
So, you should not be afraid of switching air conditioner on in winter. Electronics will not let to do harm to the system – conditioner simply will not switch on. And when there are some conditions for its work – it will start working by itself. And working conditioner will really help to eliminate fogging of windows.
Is it necessary to turn on the air conditioner in the car in winter?
During the cold season, the air contains a large amount of moisture, which gets inside the cabin. In addition, it gets there also in the form of rain or snow on the shoes and clothes of passengers, as a result of which water vapor accumulates in the closed vehicle.
Its surpluses appear in the form of glasses misting up, which impairs the driver’s vision. Having switched on air conditioner in a cold season, it will not only save glasses from weeping, but also dehumidify air. For this purpose it is only necessary to direct a stream from air-cleaning device on glasses, having switched for the mode of closed circulation.
Everybody knows, that running air conditioner increases a vehicle’s fuel consumption. This fact is quite often the reason why you should not use such a device in winter time.
Service life of the device is prolonged.
Except the aforesaid, a working conditioner in frosty weather will not only remove surpluses of water steam from a saloon, but also will prolong period of service of a device. Certainly, it is not necessary to start it every day: it will be enough to switch on the device approximately once for 7-10 days, having left it to work at least for 15-20 minutes.
The matter is that a film of oil which is covering the surface of internal parts of the device slowly runs down, remaining only in some places of a system of air-conditioning.
The more time this unit of the vehicle is idle, the longer its compressor will function on dry friction after startup, until the lubricant spreads throughout the entire system.
The compressor is quite expensive equipment, so its breakdown due to prolonged downtime will cause serious damage to the budget. But even replacing it will not bring the expected results.
All the metal particles from the surface of the parts, which will be “scraped off” by the compressor in the dry friction mode, will disperse all over the system.
Even in case of its flushing before installation of a new unit, it will not help much: metal particles will surely remain, get into the new compressor, where they will worsen its condition.
Therefore, it is not only possible, but even it is necessary to switch on a conditioner in wintertime, in order to prolong its service life.
Problems with switching on.
It is quite a different matter, that at subzero temperatures there are problems with switching on of air conditioner, and as a consequence of this there is a well-known belief, that this device cannot be used in winter.
Many car owners are sure that a special sensor, which is adjusted for a certain temperature outside, is the cause of problems with switching on. In fact, such unit exists, but its work depends not at all on air parameters, but on a level of pressure of the refrigerant – freon – in a conditioner.
And already this parameter depends on temperature. Besides, the level of this substance in a conditioner can be less than the demanded norm, and at this the device can not start. Why does it happen?
Even in case of full air-tightness of the system, freon level decreases approximately by 10 % per year – it is a norm.
In warm seasons lack of this refrigerant is not seen, because at a high temperature its pressure is enough to start air-conditioner. But in wintertime freon pressure is low, and sensor can consider that its level is below the minimal mark, and as the result of this it will not start.
How to switch on air conditioner in winter?
In order to switch on air conditioner in cold season, you can try to drive a car in a garage or to start it during car’s washing.
If there is no such an opportunity – you can try to drive for some time, and already after that to start air conditioner – the temperature in the engine compartment will rise, as a result of which some units of the system will warm up and pressure of a refrigerant will increase up to normal level, and this will give an opportunity to start air conditioner.
Right after switching on the device should work with closed circulation – in this case the air, which passes through the device, will be taken not from the street, but from a salon, where it is warmer. It will promote even more heating of the conditioner and its normal work.
Thus, one should not doubt anymore, whether it is possible to switch on air conditioner in a car in winter – it is necessary to do it necessarily in frosty weather for prolongation of its service life and improvement of microclimate inside a car.
