Yes! You can build a cooler and vent your air conditioner into a basement, storage room or lightly used space. You would not want it to blow into an area where there are customers.
A few tips:
- Proper set backs are vital for the functionality of the air conditioner, at least 2 feet on each side, top and back of the A/C (check owners manual for exact set back requirements for your model!)
- Warm air will be vented into your basement from the back of the A/C unit. It's just warm air, and it's not harmful. If you have windows, you will want to open them a little, or install a vent or an exhaust fan to keep the space comfortable and the back of the A/C ventilated. If you live in a cold climate, this extra heat may be welcome in the wintertime.
- Water will drip from the back of the air conditioner, and normally you can catch it in a dish, It's usually just a small amount of water unless you live in a very humid climate or are opening the cooler door a lot, which will increase the amount of condensate.