An Equipment Use Permit (PW-4) is required to install an air conditioner unit over three tons or 36,000 BTU per hour.

Application information is available on the Department of Buildings (DOB) website.

Visit the DOB website.

These are the guidelines you should follow when installing an air conditioner:

• Follow the manufacturer's instructions included with the A/C unit.

• Make sure the A/C is installed securely. Support it from underneath or firmly fasten it from inside with angles. You can use metal brackets and mounting rails for safe installation.

• Supporting metal brackets and interior angles must be structurally fastened to the building envelope and strong enough for the size and weight of the A/C unit.

• Objects used to adjust the position of the A/C unit must have an independent source of fastening or attachment.

• Secure leveling objects in order to prevent movement and shifting due to vibration or weather conditions.

• Install the A/C so that it remains in place when the window is opened and affix it so that the window cannot be opened accidentally.

• Do not use loose objects, such as wood blocks, bricks, or telephone books to level an air conditioner.

• Do not place anything on top of an air conditioner.

• Tilt the unit slightly to provide water drainage but do not over tilt.