I recently completed a comprehensive heating and air conditioning repair service for a client. Upon arrival, I conducted a thorough inspection of the HVAC system to identify any issues. I diagnosed a malfunctioning thermostat and a clogged air filter, both of which were contributing to the system's inefficiency. I replaced the faulty thermostat and cleaned the air filter to ensure optimal performance. Additionally, I checked the refrigerant levels and found them to be low, so I refilled them to the appropriate level. The system is now running smoothly, providing efficient heating and cooling for the client's comfort.