You can use a pressure washer to clean the outdoor condenser coils if the dirt buildup is too heavy for a garden hose and sprayer. Use a gentle setting on your pressure washer to avoid damage to the coils and fins. Do not use a pressure washer on indoor evaporator coils.

It’s not customary to tip HVAC technicians, and most professionals won’t expect it. However, it’s a nice way of showing your appreciation for the work they do, especially if they come out in inclement weather or on a weekend or holiday to fix an emergency issue if your heat or AC goes out in extreme temperatures. A good tip would be between 10% to 20% of the total bill, depending on how above and beyond the tech goes for your repair and on the total cost of your HVAC repair or service. For something like a routine tune-up or scheduled maintenance, tips aren’t expected.

NATE (North American Technician Excellence) certification is not legally required for HVAC technicians in most areas, but hiring a professional with this certification is highly recommended. NATE-certified technicians demonstrated their expertise and proficiency in different types of HVAC systems, offering assurance of quality service. It's a voluntary certification, yet it indicates a commitment to professionalism and ongoing training. Choosing a NATE-certified technician often means you're working with someone who is up-to-date on industry standards and best practices, which can lead to better service, energy efficiency, and long-term cost savings.

While you can run your HVAC system without an air filter, it isn’t something professionals recommend—especially not for an extended period. It can reduce indoor air quality, clog air ducts, and strain your system. This can lead to performance issues, higher energy bills, costly repairs, and a reduction in the system's lifespan.