Explanation: First, The intended meaning is not clear. Does it mean preparatory work currently going on for installing air conditioning? Does it mean the apartment is ready with all the wiring and duct work for the buyer to install a new condenser? Or does it mean something else? More context will help.
I will assume the apartment has everything except the acutal condenser. If that is the case, then I would switch from the nominal to the adjectival form.
The expression "air conditioning ready" is used, for houses, apartments, cars, and electrical outlets.
I am not sure whether The Apartment Is ready for installing the air conditioning system, or not. I'll ask my client.
Thanks.
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20 mins confidence: peer agreement (net): +5
air conditioning ready
Explanation: First, The intended meaning is not clear. Does it mean preparatory work currently going on for installing air conditioning? Does it mean the apartment is ready with all the wiring and duct work for the buyer to install a new condenser? Or does it mean something else? More context will help.
I will assume the apartment has everything except the acutal condenser. If that is the case, then I would switch from the nominal to the adjectival form.
The expression "air conditioning ready" is used, for houses, apartments, cars, and electrical outlets.
Fuad Yahya United States Native speaker of: Arabic, English PRO pts in pair: 2395
The translation workplace 
peer agreement (net): +5