HVAC built around your home — not a sales script.
KJ Thomas Mechanical is a family-owned, tradesman-led HVAC company serving Boulder County. We help homeowners choose and install heating and cooling systems designed for long-term comfort, reliable performance, and the way their home actually works.
What we deliver
Installation • Maintenance • Repair
From clean installs to seasonal tune-ups and urgent fixes, we keep HVAC tidy and dependable.
Installations
Heat pumps, furnaces, and mini-splits installed with designer-level detail.
Maintenance / Tune-ups
Seasonal service that prevents surprise breakdowns.
Repair
Diagnosis first, clear options, and parts stocked for quick fixes.
Who we serve
Residential and light commercial across Boulder County with tidy installs and responsive service.
Single-family, townhomes, rentals, and additions
Heat pumps, furnaces, AC, and ducted or ductless solutions that keep living spaces comfortable without messy installs.
Studios, tenant finishes, boutique retail, small offices, restaurants, and light warehouses
Light commercial replacements (including RTUs), zoning tweaks, and maintenance that respect business hours and keep spaces running smoothly.
Services
Practical options, clear scope, and workmanship that holds up—from heat pumps and mini-splits to AC, furnaces, and maintenance plans.
Heat Pumps
Efficient heating and cooling for Colorado weather. Great comfort, lower bills, and cleaner installs.
Furnaces
High-efficiency gas furnaces, clean duct transitions, and straightforward options.
Mini-Splits
Zoned comfort without major remodeling. Ideal for additions, offices, and older homes.
Air Conditioning
Right-sized AC with quiet operation and tidy line sets. No shortcuts.
Rebates
We help you qualify for Xcel and local rebates, handle paperwork, and close the loop after install.
Maintenance
Seasonal tune-ups that catch issues early and keep equipment running as designed.
Our reviews
Service area
Based in Boulder County. We regularly serve Boulder, Longmont, Lyons, Louisville, Lafayette, Niwot, Superior, Erie, Mead, Frederick, Firestone, Gunbarrel, and nearby areas.
Why KJ Thomas
We do the work like it is our own house
We take pride in clean routing, tight details, and honest recommendations. You will see it in the install.
No shortcuts in the parts you cannot see
Sealing, airflow, condensate, and electrical get done right. These details decide how the system feels long term.
Communication that respects your time
Clear scheduling, text updates, and straightforward estimates. Boulder busy is real. We keep it simple.
Need an estimate today?
Tell us what you have, what is not working, and your timeline. We will respond with next steps and scheduling.