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I bought an air conditioner (split type) rated 220v-240v, 50 Hz. What could happen if I use it in our country which uses 220v, 60 Hz? A lead technician from a refrigerator and air conditioner shop told me that there's no problem which means they could install the unit and it will work properly. But another technician from another shop informed me that it's not possible. If they install it, there's no assurance that it will function normally. Another technician also suggested that I might need to buy a transformer or AVR. Who is telling the truth? Is there anyone who could give me "professional" advice about this?

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closed as off-topic by tcrosley, PeterJ, Nick Alexeev Mar 6 at 0:41

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – tcrosley, PeterJ, Nick Alexeev
If this question can be reworded to fit the rules in the help center, please edit the question.

Does the motor drive everything directly, or via a belt? If it's belt drive, you can change one of the pulleys to avoid the very real problem Charles Cowie mentions : the makers would probably sell a 60Hz pulley for the purpose. A transformer certainly won't help. – Brian Drummond Mar 5 at 15:39
Always buy air conditioners locally. Try not to import them. Logistics will be an unnecessary burden (it's big, heavy, and it'll cost to transport). – PandaLion98 Mar 6 at 0:40
@BrianDrummond Have you seen any of air conditioners? I didn't see any pulley, the compressor is all in one- motor and compressor in same bin, welded. – Marko Buršič Mar 6 at 9:46
If it's an all-in-one model then the increase in frequency is a big problem and the pulley change is not a solution. One possible solution would be a VFD (inverter) normally used for 3-phase motors like machine tools, but it's probably cheaper to replace the motor/compressor unit for the correct one. – Brian Drummond Mar 6 at 11:51

The motor will try to run 20% faster than the unit is designed to run. Increasing the fan speed by 20% will theoretically increase the load torque by 44% and the load power by 73%. The compressor part of the load will theoretically increase by 20% torque and power. Operating the motor at 220 volts on 60 Hz will theoretically reduce the motor's torque capability by 30%.

Your best course of action would be to sell it and buy one that is suitable.


Changing the pulleys to get the proper speed as Brian Drummond suggests may be a good solution.

Most likely, a single phase motor is used. It would likely be either a permanent split capacitor (PSC) motor or a capacitor-start, capacitor run motor (2 capacitors). That complicates the issue of proper voltage. The impedance of the coils increases with increased frequency and the impedance of the capacitors decreases. It is difficult to predict how that will affect the motor.

If the unit contains an inverter, that could potentially solve the whole problem. However, if that were the case, I would think that it would be labelled 50/60 Hz.

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If the compressor isn't driven by an on-board inverter, then the 20% increase in wanted speed could overload the capacity of the capillary tubes & "fluid lock" the compressor in "worst-case-scenario," which would result in a huge (undefined) increase in compressor torque (and related current draw). - +1 for the fan stats & (very correct) recommendation for trading it for a 60Hz model. – Robherc KV5ROB Mar 5 at 16:53

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