Central air conditioning units used circuit boards for sale. If your system requires a circuit board that possibly doesn't exist or if the board is too expensive, maybe we can help you to find it with us or maybe be able to afford it. Just give me the part # or a system model number to see if we can be able to help you. You can call or text me at; Nine, Five, Six-Eight, Seven, Three-Zero, Thee, Five, Three.