In the export and international trade of air conditioners, many customers may ask a question: What's the difference between 50 Hz and 60 Hz air conditioners? Are they compatible?

Actually, Hz (hertz) refers to the frequency of the power grid. Different countries have different frequencies, which directly influence the compressor, motor speed, and the overall performance of the air conditioners. This is very important for air conditioner importers and buyers.

 

I. What are 50Hz and 60Hz?

 

The frequency of a power grid refers to the number of times the alternating current changes per second.

50 Hz: It changes 50 times per second;

60 Hz: It changes 60 times per second.

Simply, 60Hz current changes faster than 50Hz.

 

There are two major power grids in the world:

50 Hz countries: China, Europe, the Middle East, Africa, Southeast Asia, etc.

60 Hz countries: America, Canada, Japan, South Korea, the Philippines, part of Saudi Arabia, etc.

 

II. Influences on the compressor speed

 

Basically, an air conditioner compressor is motor-driven equipment, while the power grid frequency will directly affect the motor speed.

The theoretical speed formula for an electric motor is: Speed ​​≈ 120 × Frequency ÷ Number of poles. So a 60Hz motor has a speed of 20% more than a 50Hz one.

An improved motor speed will bring us the improvement of cooling capacity, cooling power, and energy consumption.

 

 

III. Influences on the performance of air conditioner

 

1. Cooling capacity

 

A same-capacity air conditioner, converting the operation from 50 Hz to 60 Hz, will have its cooling capacity increase about 15%-20%.

For example, the cooling capacity of a 12000 BTU air conditioner:

At 50 Hz: around 12000 BTU;

At 60 Hz: reach 13500-14000 BTU.

 

2. Power consumption

 

In case of the increase of compressor speed, the power input increases as well as the current.

So the 60Hz air conditioner normally consumes more electricity during operation.

 

3. Noise

 

After the increase of compressor and motor speed, the vibration will increase, and the same will happen to the noise.

But this is not obvious under modern air-conditioner technology.

 

IV. Can we use a 50Hz air conditioner in 60Hz countries?

 

There are three conditions:

 

1. Fixed-frequency air conditioner

 

If a 220V 50Hz air conditioner is connected to a 220V 60Hz power grid, it may lead to:

Overspeed of the compressor;

Higher current;

Broken after long-term operation.

It is not recommended for long-term use.

 

2. 60Hz air conditioner used in 50Hz countries

 

In the same voltage conditions, 220V 60Hz air conditioners can operate in a 220V 50Hz power grid, but the performance will change. The motor speed will decrease 16%-20%. This decrease may lead to:

Decrease of compressor speed；

Decrease of power output；

Reduced burden on motor.

 

3. Variable-frequency air conditioner

 

Modern variable-frequency air conditioners (inverter air conditioners) have rectifier and inverter circuits inside the body. It converts alternating current into direct current, then generates a new alternating current frequency by inverter. Many inverter air conditioners can adapt to 50/60Hz.

That's why many air conditioners are now labeled as 50/60 Hz.

 

V. What are the points we should consider when purchasing air conditioners?

 

1. Voltage

110V, 220V, 380V, 440V.

 

2. Frequency

50Hz, 60Hz, or 50/60Hz.

 

3. Power supply phase

1 phase, 2 phases.

A complete mark normally writes 220–240 V / 1 Ph / 50 Hz.

 

The key difference between 50Hz and 60Hz air conditioners lies in the power grid frequency, which directly affects compressor speed and overall performance.

With the development of inverter technology, more and more air conditioners are adapting to a 50/60 Hz dual-frequency power grid. This makes air conditioners easier to export.

 

To those living in extremely cold regions, a common question comes when it is needed to heat by an air conditioner in winter: can the air conditioner outdoor unit operate freely in an extremely cold environment or not? Particularly under the ultra-low temperatures of -30℃ and -40℃, is the air conditioner able to supply reliable heat?

 

1. What are the limits of traditional air conditioners?

 

Traditional non-inverter or inverter air conditioners are available to operate under the ambient temperature of -7℃ to -15℃. When the temperature goes further lower, the situations below will occur:

 

i). Apparent decrease of heating capacity;

ii). Severe frost on the outdoor unit and defrosting affect heating performance.

iii). The compressor is hard to start or does not even start.

 

In case of that, traditional air conditioners can not start freely under the temperature of -30℃ and even -40℃.

 

2. Advanced technology: EVI technology

 

For cold regions, air conditioner manufacturers will develop the air conditioner models with EVI (Enhanced Vapor Injection) technology. By adding additional jet ports for gas in the compressor, the technology allows the refrigerant to keep enough pressure and flow under the extreme cold condition, improving the heating ability under low temperature. Adopted with EVI technology, the air conditioners could provide stable heating under -25℃ to -30℃ environments. Some high-end models are claimed to start freely under -35℃.

 

3. Impossibility under -40℃

 

Under a -40℃ environment, even the high-end air conditioning models are still facing great challenges:

 

i). The starting difficulty: Thickening of the refrigerant oil makes it difficult to lubricate the compressor.

ii). The decreasing heating capacity: Even if the system can start, the heating capacity will be significantly reduced.

iii). The increasing power consumption: Even if the system can start, the heating capacity will be significantly reduced.

 

Common solutions to the -40℃ environments are ultra-low temperature air source heat pumps (customized commercial/engineering machines), rather than ordinary household air conditioners, or electric auxiliary heating and gas heating with air conditioning used in conjunction.

 

4. Options for the cold areas.

 

For regions in the Mongolia plateau, Northern Russia, and Canada, it is recommended to choose low-temperature heat pump air conditioners with EVI technology or directly choose air source heat pump heating units, whose operating limit can be extended to -35℃ or even -40℃, or combine them with backup heating methods such as floor heating and electric heaters to ensure comfort and safety in extreme weather.

 

Traditional air conditioners can't start at -40°C. Even some high-end low-temperature heat pump models claim to be able to operate, but they require extremely demanding technical support and operating environments. For users in extremely cold regions, choosing a professional ultra-low-temperature heat pump product is the only reliable way to heat your home in winter.