With the onset of the first serious cold weather, many motorists are wondering how to properly operate the climate system of the car. In particular, the possibility of activation is doubtful. air-conditioner at negative temperatures overboard. This question is not without common sense, because the refrigerant circulates inside the system, and the lubrication of rubbing parts directly depends on the viscosity of the oil.
On the one hand, car manufacturers often provide protection against rash actions of the driver, blocking the start of the compressor at low temperatures. On the other hand, there is a strong opinion about the need for periodic “run” of the system to prevent drying out. sludge and seals. Let’s look at the line between useful prevention and the risk of expensive repairs.
The answer lies in understanding the physical processes that take place inside. climate-set. Cold affects the properties of technical fluids, and ignoring this fact can lead to the failure of expensive nodes. However, the complete abandonment of the system in winter is also not always the right solution, especially if you take into account the need to combat fogging of glass.
System operation and the effect of cold on refrigerant
To understand the risks of winter operation, it is necessary to briefly consider the device. air-conditioner. The main working element is a compressor that compresses the gaseous freon, turning it into a liquid under high pressure. This process is accompanied by significant heating, which is discharged through the radiator. In winter, the ambient temperature contributes to natural cooling, which would seem to be a plus, but there is a nuance.
The key is the state of affairs. compressor oilwhich circulates with Freon. It is necessary for lubricating the rubbing pairs of the compressor and sealing the gaps. With a strong decrease in temperature, the viscosity of this oil increases sharply. If you run the system on a cold, the oil can become so thick that it will not be able to perform its functions effectively, which will lead to work "dry" or with increased friction.
In addition, there is moisture in the system, which in the form of condensate can accumulate in various nodes. When frozen, water turns into ice, which creates a risk of formation. ice-staff in the expansion valve or tubes. This can block the refrigerant circulation and create excessive pressure, which is dangerous to the integrity of the system.
⚠️ Warning: Attempting to turn on the air conditioner at temperatures below -5 ° C without first warming up the cabin can lead to jamming of the compressor due to thickened oil.
Thus, the physics of the process dictates its conditions: cold start of the air conditioning system is extremely undesirable. However, modern engineers have taken this factor into account by introducing various sensors and blockers into the design, which we will talk about later.
Protective mechanisms and temperature thresholds
Owners of modern cars can be reassured: in most cases, electronics will not allow you to harm the car. Climate management system (climate control) is equipped with evaporator temperature and ambient air sensors. If the sensor detects a value below the set threshold (usually from 0°C to +5°C), the electrical circuit of the compressor clutch or the signal to the electromagnetic valve simply does not close.
You can see that when you press the button. A/C indicator lights up, but the characteristic click of the compressor and the drop in engine speed does not occur. It's a regular defense job. In some models, especially premium ones, the algorithms may be more complex and allow for short-term switching on to test the tightness of the system, but only if the temperature permits.
The situation is different in older cars or machines with mechanical climate control. There is no protection at all and the driver is responsible. In such cases, knowledge of temperature thresholds becomes critical to the conservation of the aggregates.
It is also important to note the difference between systems fixed-productivity modern variable-capacity compressors. The latter are more sensitive to lubricant quality and temperature conditions, since their pressure control mechanism is more complex and requires ideal conditions for the control valve to operate.
Why even include air conditioning in the cold?
If there are risks, it would be easier to wait out the winter without air conditioning. But there is a function that is even more important in winter than in summer. air-dripping. When you exhale or enter the cabin with snow on your clothes, the humidity inside the car rises dramatically. The condensate settles on cold glass, creating a dense foggy veil that impairs the view.
Regime. windshield In many cars, the air conditioner automatically activates even if the A/C indicator is not on or you have not manually turned it on. This is done precisely to remove excess moisture from the air before it hits the glass. Dry air heats up faster and fights fogging more effectively.
There is also a technical need to run the system periodically. Long downtime (more than 2-3 months) without circulation of freon and oil can lead to the fact that plumbing They lose their elasticity and start to pass gas. A short start once a month in a warm room or at a plus temperature helps to distribute the oil throughout the system and maintain tightness.
For a quick fight against fogging in winter, turn on the air conditioner at the same time as the stove and recycling mode, but make sure that the windows do not start to fog even more because of the high humidity in the cabin.
Rules for safe launch in winter
If you need to use air conditioning in winter, for example, to fight fogging, or you want to conduct a preventive start, you must follow a strict algorithm of actions. Ignoring these rules can negate all protective functions and lead to breakdown.
The first and most important rule is heat-up. Never try to turn on the A/C immediately after starting a cold engine. The engine must warm up to the operating temperature to warm up and the underhood space where the compressor is located. This will allow the oil in the air conditioning system to become more fluid.
The second rule concerns the temperature in the cabin. Before activating the button A/C Wait until the temperature of the air blown out of the deflectors becomes positive. This usually takes 5-10 minutes of engine operation in motion or at idle speeds with the stove on.
The third rule is moderation. If you have turned on the air conditioner for dehumidification, do not keep it running for hours at extremely low temperatures. 5-10 minutes of work is enough to complete the task of removing moisture or lubricating seals.
☑️ Checklist before A/C switch on in winter
Compliance with these simple recommendations will minimize the wear of parts and avoid emergency situations. Remember that even if the system is protected by electronics, mechanical wear and tear from work in abnormal modes has not been canceled.
Typical malfunctions and their symptoms
Violation of operating rules or natural wear can lead to problems that manifest themselves in the winter, when the load on adjacent systems is high. Understanding the symptoms will help diagnose the problem in time and avoid more serious repairs.
One of the frequent problems is leakage. refrigerant through the parched gums. If the system was idle for a long time, Freon could escape. When you try to turn on the compressor will work "idle", which for some types of compressors (especially without freon pressure protection) can be fatal.
It is also worth paying attention to the work of the air conditioner radiator fan (capacitor). In winter, the radiator’s honeycombs are often stuffed with snow, ice crumbs or reagents from the road. A clogged radiator will not be able to effectively cool the freon, which will lead to an increase in pressure in the system and an emergency shutdown.
| Symptoms. | Probable cause | Risk to the system |
|---|---|---|
| Whistling from under the hood when switched on | Belt slip or bearing wear | Breaking the belt of the GM (on some cars), overheating |
| Clicking clutch without cooling | Freon deficiency or pressure sensor error | Compressor operation without lubrication, jamming |
| Extraneous noise (hum) of the compressor | Wear of internal machinery or bearing | Complete destruction of the compressor, the entry of chips into the system |
| The air conditioner doesn't turn on at all. | Temperature protection or no pressure | Minimal, if not trying to "cure" blows |
If you notice. clang-bang Immediately after switching on, immediately turn off the engine. Continuing to operate in this mode is guaranteed to lead to expensive repairs of the entire system, including washing pipes and replacing radiators.
Myths about winter climate control
There are many legends around car air conditioners that often confuse inexperienced drivers. Dispelling these myths helps you make the right decisions and avoid wasting money on unnecessary procedures.
Myth One: “Air conditioning should be turned on in winter every week, even in the cold.” That's a dangerous misconception. As we have already found out, starting at temperatures below -5 ° C without special preparation is harmful. Prevention is best carried out in a warm garage or on days with a plus temperature.
Myth Two: “If you don’t turn on the air conditioner in winter, it will rot.” The ossels dry not from the absence of freon, but from time and temperature changes. Oil circulation is useful, but it is not a panacea for rubber aging. More important is the system as a whole.
⚠️ Warning: Do not try to “design” a frozen air conditioner by turning on and off the button repeatedly. This creates peak loads on the power grid and compressor mechanics.
Myth Three: “In winter, air conditioning consumes more fuel.” In fact, in winter the load on the air conditioner is lower, since the temperature difference is less, and the freon is more easily condensed. However, the operating system still takes some of the power from the engine, increasing the flow rate, but not critically.
Technical reference
Why can not turn on in the cold?: In the compressor uses a special polyester oil (POE), which is hygroscopic, that is, absorbs moisture. In the cold, the moisture in the oil crystallizes, turning into an abrasive. When starting a cold compressor, friction pairs are scaled, which reduces the resource of the unit at times.
Service recommendations before the winter season
To make sure your climate system survives the winter and is ready to go into operation in the spring, you should do a series of preventive measures in the fall. This will save you from unpleasant surprises in the form of foggy glasses at the most inopportune moment.
First, you need to check the level and condition. compressor oil And the amount of freon. Even a small leak over the summer can lead to the fact that in winter the pressure is not enough even to start the sensors. Diagnosis on a specialized stand will show the presence of moisture in the system.
It is also important to clean the condenser (air conditioner radiator) of dirt, down and leaves. In winter, this mud will freeze and can damage thin aluminum lamellae. A neat wash under low pressure will prolong the life of the heat exchanger.
The main idea: Winter operation of the air conditioner is permissible only for drying air with a warmed-up engine and cabin, and preventive starts should be carried out exclusively at plus temperature.
Don't forget to change. cabin filter before winter. Clogged filter negates the work of the stove and air conditioner, forcing the system to work with overload, which is especially noticeable in the cold season.
Frequently Asked Questions (FAQ)
Can I turn on the air conditioner at -10 degrees?
It's highly discouraged. At this temperature, the oil in the compressor becomes too thick, which can lead to breakage. The electronics of the car will most likely block the launch itself, but you should not risk it. Wait for the warm-up of the cabin or warmer weather.
Why does the air conditioner turn on when blowing glass?
It's a regular work schedule. The system automatically activates the air drain compressor to quickly remove moisture from the glass and prevent fogging. In this mode, air passes through a cold evaporator where moisture condenses and is then heated by a stove.
How often should I run the air conditioner in winter for prevention?
It is enough once every 2-3 weeks, but only on condition that the air temperature is above +5 ° C and the car is well warmed. If there are no such days, it is better to refrain from preventive launches until the heat sets in.
What happens if you accidentally turn on the air conditioner in the cold?
If the vehicle is properly electronic protection, the compressor will not start. If there is no protection (old cars) and a start-up has occurred, a single short-term turn-on is likely not to lead to fatal consequences, but regular repetition of such an error will reduce the life of the compressor.