Using this 1/3 - 1/4 HP universal PTC motor start relay is a breeze. First, make sure your compressor is in the 1/4 - 1/3 HP range, as this relay is designed for such compressors. Then, connect the three 6.4mm spade terminals and the two connections to the compressor, and it'll be done in seconds. As for maintenance, keep it in a dry place to prevent moisture damage. When using, avoid over - voltage situations as it may cause overheating and damage to the relay. If you have any issues, feel free to contact our customer service, as we've been in the appliance parts business for over 25 years and are here to help.