Proudly serving Fairfield County

for over 45 years


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When your office or industrial building needs a heating system installed or repaired, contact Custom Air Systems, Inc. For over 45 years, we've provided exceptional customer service. From our receptionists to our technicians, you'll receive personal and professional attention. Keep your building warm and comfortable with our maintenance programs, too. Call us for a FREE estimate. We work on all types of heating systems.

The Best People Provide the Best Service

"I want to commend service technician Anthony Colon for the outstanding job he did at my home recently. He is a credit to your company."

- William C. Lesko, CPA

  • Boiler installation and replacement

  • Boiler repair and maintenance

  • Ductless mini split systems

  • Very efficient systems

  • Fireplace installation and replacement

  • Fireplace repair and maintenance

  • Furnace installation and replacement

  • Furnace repair and maintenance

  • Gas furnaces

  • Geothermal systems

  • Heat pump installation and replacement

  • Heat pump maintenance

Stay cozy at work even on the coldest winter day

Call for 24/7 Emergency Service and Free Estimates.


  • Heat pump repair

  • Heating installation and replacement

  • Heating repair and maintenance

  • Hybrid heating systems

  • Maintenance

  • New technology (lower fuel costs)

  • Oil furnaces

  • Oil to gas conversions

  • Radiant heat installation and replacement

  • Radiant heat repair and maintenance

  • Thermostats and zone systems

  • Water heaters