Completed system tune up. Checked volts, amps, pressures and all electrical components. Checked thermostat operation. Checked air filter and evaporator coil. Cleared drain with cleaner. Found microbial growth in air handler and on bottom of coil. Recommended installing Remy halo to prevent growth and kill existing growth. We will sanitize when installed. Customer will call to schedule. Renewed membership. Left system in good working order.