Did you know that the air in your home or office is actually more contaminated than the air outdoors? It's true! In fact, studies have shown that indoor air quality is anywhere from 30-50% more polluted than the air outside. A big part of this pollution is due to dirty ductwork and inefficient air conditioners.

When Your A/C Breaks or Needs Replacement

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When Your A/C Breaks or Needs Replacement

Financing Available 18 Months No Payments No Interest.

If your AC unit isn't properly maintained, it can become a breeding ground for mold, mildew, fungus, and bacteria. Not only is this unhealthy for you and your family, but it can also lead to costly repairs down the road.

Dirty ductwork and inefficient air conditioners are major contributors to poor indoor air quality. This can cause a number of health problems, including asthma, allergies, headaches, and even Legionnaires' disease. Fortunately, there are a few things you can do to prevent your AC unit from becoming a health hazard. First and foremost, make sure to change your air filter regularly—at least once every three months. You should also have your AC unit serviced by a professional at least once a year. By taking these simple steps, you can help improve the indoor air quality in your home or office and breathe easier knowing that you're doing everything you can to protect your health.

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  • I recently used Grandmark Service Company for a roofing repair project and new ductwork for my central air and heat unit. Two new solar light tubes and two exterior roofing vents for my whole house fan. First Grandmark was quick in sending out a Technologist to assess my roofing repair. The repair was done in a very professional manner with special attention paid to a down spout. I can't thank that tech enough for the excellent work and attention to detail. I then decided upon inspection of my existing ductwork to have it replaced. Again, the crew removed all the old ductwork out the top of the attic where the new exterior vents would be placed saving me a ton of clean up. Throughout this process they provided tarps on the floor and did a thorough clean up at the end of the day's work. All crew member's were professional and friendly and answered any questions. If I could I would give them ten stars. But for this review five stars will have to do. Again, thank you Grandmark service company. I won't hesitate to use you again should the need arrive.

    thumb John Ruch
    November 26, 2022

    Recently moved to the central valley, got 3 quotes from other companies that were way over priced. They finished the job in less than two weeks. Highly recommend this crew..will be using them for solar install in the future

    thumb Ruben Hernandez Avina
    November 19, 2022
  • Tony Arevalo was very professional and helpful. Grand mark service is awesome. Best experience I have had with HVAC so far.

    thumb nike omijori
    November 10, 2022

    Tony very professional. We we very pleased and estacic with everything Tony did for us.

    thumb Albert Scott
    November 10, 2022