There is a company called SimplySmartHome that offers maintenance services for heating and cooling. They provide a Google Nest setup, if you sign up for their services. So far, I have found them fast on response and efficient.
Note: When you sign a contract with them, they put a lien on your property for the duration of the contract. This is to keep you from terminating the contract. This is in the fine print. They talked about other things when signing the contract, failed to mention this altogether. That is the reason for my 1-Star rating.
Of course, if you are fine with a property lien, this is a decent choice for maintenance.