If you use good filters and replace them regularly, the evaporator coil should rarely, if ever, need to be cleaned. I have never needed to clean an evaporator coil. But, I have seen HVAC units where the unit was operated for a long time without a filter at all, and the coil will accumulate dust, hair, and dirt. Then, it definitely needs to be cleaned. But, I don't think most maintenance "tune-ups" will include cleaning the evaporator coil. They may inspect it, but not clean it. If you think your HVAC company is cleaning the coil every year, I would ask to see the chemical he used.
|