I have a doorbell model C8821 from emerson rittenhouse and the chime looks like it's not working. Transformer if working because the button is lid up outside. The previous call button went bad and I replaced it as it used to get stuck thats what I think happened and the chime burned out. when replaced the button I put both wires together and no chime at all.Please let me know what would be the cost to repair this. Thank you.