AC Repair
Same-day air conditioner diagnosis and repair across Boulder County.
Learn more 24/7 Emergency Same-day service across the Front Range
Home comfort in every season.
From heat waves to cold snaps, Northline keeps your home comfortable with fast, honest heating, cooling & air-quality service — backed by upfront pricing and a satisfaction guarantee.
Licensed, bonded & insured NATE-certified techs Upfront flat-rate pricing
4.9/51,200+ verified reviews
What we do
Complete HVAC care, under one roof.
Repairs, installs, air quality and maintenance for every heating and cooling system in your home.
Furnace Installation
High-efficiency gas and electric furnace installation, sized for your home.
Learn moreHeat Pump Service
Heat pump tune-ups, repairs and replacements for year-round comfort.
Learn moreIndoor Air Quality
Filtration, humidification and air purification for healthier indoor air.
Learn more
Why Northline
The contractor you'd recommend to a neighbor.
We've built our reputation on doing it right the first time — clear pricing, clean work, and technicians who treat your home like their own.
Same-day & 24/7
Emergency techs on call around the clock — no heat or no cool never waits.
Upfront flat-rate
You approve the price before we start. No surprises, no overtime fees.
NATE-certified
Background-checked, factory-trained technicians who respect your home.
Guaranteed work
100% satisfaction guarantee backed by parts & labor warranties.
Financing available
Comfort now, pay over time.
Qualified homeowners can finance a new system with 0% APR intro plans and low monthly payments. Fast approvals — often while your technician is still on site.
Subject to credit approval. Ask your comfort advisor for current terms.
Where we work
Proudly serving the Front Range.
Local technicians, fast response times, and neighbors you can count on across the Denver metro.
Good to know
Answers before you book.
A few of the questions we hear most. See the full list on our FAQ page.
Yes — we answer calls 24/7, 365 days a year. A live technician (never a machine) will help triage your no-heat or no-cool emergency and get someone dispatched fast.
For most homes, every 90 days — but if you have pets, allergies, or run your system hard, check monthly. A clean filter is the single easiest way to protect your equipment and air quality.
Most residential replacements are completed in a single day. Larger or multi-system homes may take two. We give you an exact timeline before we start.
It depends on your square footage, insulation, windows, and layout — not just a rule of thumb. We perform a proper load calculation so your system is sized right, not just big.