Can you use your air conditioner if the fan outside isn't working?

No, you can not use your air conditioner if the fan outside is not working.

Simply because, the heat picked from your indoor air has to be rejected out side, if the out side fan is not working the rate of heat rejection will be very minimal, and as a result the indoor unit can not take any more heat, as a result, the air conditioner will not be cooling after few minutes.

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