Is hiring HVAC service company necessary for maintenance?

If you're being really, really good, you should probably change your filters four times a year and get your ducts professionally cleaned once a year.

If you don't? Well, your system will function okay for years, but then expensive parts will burn out sooner. It's one of those "stitch-in-time-saves-nine" things.

ali r.
{downtown broker}

Is this on window units? If that's all you can do it yourself. change the filters and vacuum it well...

If there is a central air unit outside or on the roof - The condenser needs to be washed out properly and the refrigertant line filters might need to be changes as well as the air filters....

This is central air unit. Just curious as to what people are doing with their units.
How much do they charge usually for these maintenance service?