Written October 2026, with the Town of Herndon’s and Fairfax County’s permit pages, the Census and every review platform read the same week.
A new furnace and air conditioner in Herndon runs $8,898 to $23,000 installed, depending on the size of the house and the equipment you pick. From about $148 a month at 0% APR for 60 months, the whole price financed, on approved credit. It’s the same price book we use across Northern Virginia, posted on our Herndon furnace and AC page before anyone comes out.
Herndon is close to home for us. Our shop in Chantilly is about six miles away, and Herndon is one of the busiest towns on our schedule. Below: what Herndon houses heat with, what a new system costs, which office issues your permit (it depends on which side of the town line you’re on), and how our reviews add up on every site.
No heat or no cooling right now? Call (703) 997-9757. We run 24/7 emergency service.
Six miles from our shop
Our shop is on Lafayette Center Drive in Chantilly, about six miles from Herndon, and Herndon is one of the busiest towns on our schedule. Most of that work is heating and cooling, done by our own HVAC team, a crew separate from our plumbers. We cover both Herndon ZIP codes, 20170 and 20171, inside the town limits and out.
Next door runs on the same price book. If you’re in Reston or Sterling, the Reston guide and the Sterling guide cover those towns the same way.
Each service we do in Herndon has its own page, and every one opens with the price: furnace and AC replacement, heat pump replacement, AC repair, furnace repair and air duct cleaning. The rest is on our Herndon page.
What Herndon houses heat with
Inside the town limits, Herndon is a mix. About a little over four in ten homes are detached houses, more than a quarter are townhouses, and just under a quarter are in condo and apartment buildings. About four in five went up between 1960 and 1999, and the median owner’s home dates from 1981 (Census, Town of Herndon: homes by type, year built, median year).
Electric heat leads inside the town. Among owner-occupied homes, about six in ten heat with electricity, which in this climate almost always means a heat pump, and a little over a third heat with gas (Census, heating fuel).
So the first question on a lot of Herndon replacements is heat pump or furnace. A house with a gas line can go either way, or both, with a heat pump that hands off to a gas furnace on the coldest nights. A house without one is a heat pump swap. Anything beyond a standard swap, like a new return or a gas line, goes on the estimate as its own line with its own price. If your system is acting up rather than done, our Herndon heating repair guide covers what fails on a furnace at twenty-five years and what each repair costs.
What a new system costs in Herndon
Installed prices from our price book for 2 to 5 ton systems, the same numbers our HVAC estimator works from. The size of the house, the efficiency you pick, and what the ductwork and venting need decide where you land.
| The job | Installed | Or monthly |
|---|---|---|
| Furnace and AC replaced together | $8,898 to $23,000 | $148/mo at 0% APR for 60 months |
| Heat pump system | $8,499 to $21,650 | $142/mo at 0% APR for 60 months |
| Furnace alone, keeping your AC | $4,285 to $14,040 | $71/mo at 0% APR for 60 months |
Monthly figures: 60mo @ 0% APR on each starting price, the whole price financed, on approved credit. Longer plans lower the payment and cost more in total. The lender sets the final terms.
The estimator gives your house its own number in about two minutes. Then one of our technicians measures, and the price is in writing before anything is ordered. Two years of our labor come with every install, and five or ten are available. Here’s how financing works.
The system we put in first
Built to take a beating. Put in by our crew.
Heat lamps, snow and rain on one outdoor unit: that’s Trane’s own film. We’re a Trane Comfort Specialist, on Trane’s own dealer locator, and when you pick a Trane, our crew puts it in.
Films: Trane’s own.
Our reviews, every site counted
Across every platform we’re on, we’re rated 5.0 stars across 1,132 reviews on Google, Angi, Yelp, the BBB and Facebook. Yelp is the lowest of them, at 4.4 stars and about one in twenty of the total. We count it anyway, because leaving it out would make our number look better and say less.
Every platform’s rating and count, and the date each was read, is at swiftproreviews.com. The reviews themselves are on our reviews page, the low ones included.
What to check about any Herndon HVAC company
- The license. Look the company up on DPOR’s License Lookup. The name should match your estimate, the license should be active, and it should cover HVAC. Ours is Virginia Class A 2705192276, printed on the side of our vans.
- The permit, from the right office. Inside the town limits, permits come from the Town of Herndon’s Building Inspections office, and mechanical work needs its own permit there. The rest of 20170 and 20171 is Fairfax County, which requires a mechanical permit to replace a heating or cooling system, and a gas furnace needs one even when it’s like for like. The contractor should pull it, and should know which office your address answers to.
- Every line in writing. The AC or heat pump’s size in tons and its SEER2 rating, the furnace’s size and efficiency, the coil, the thermostat, the permit, hauling the old equipment away, and the years of labor. A lower total that leaves off the coil or the permit isn’t lower. How to read an HVAC replacement estimate goes line by line.
- Reviews on every platform, not one site’s worth. Our HVAC contractor guide covers the rest, including insurance and the written contract.
Herndon HVAC questions, answered straight
Does SwiftPro serve Herndon, VA?
Yes. Our shop is in Chantilly, about six miles from Herndon, and Herndon is one of the busiest towns on our schedule. We cover 20170 and 20171, inside the town limits and out, with our own heating and cooling team. Our Herndon page lists every service with its price.
How much does a new HVAC system cost in Herndon?
A furnace and air conditioner replaced together runs $8,898 to $23,000 installed. A heat pump system runs $8,499 to $21,650, and a furnace alone $4,285 to $14,040. From about $148 a month at 0% APR for 60 months, the whole price financed, on approved credit. Where you land depends on the size of the house, the efficiency you pick, and the ductwork and venting.
Who issues HVAC permits in Herndon?
It depends on the address. Inside the town limits, the Town of Herndon’s Building Inspections office, where mechanical work needs its own permit. Outside the limits, Fairfax County. Either way, have the contractor pull it in its own name.
Should a Herndon house get a heat pump or a furnace?
Inside the town, most owner homes already heat with electricity, so a heat pump is often the like-for-like swap. A house with gas can stay with a furnace and AC, or pair a heat pump with a gas furnace. A heat pump system runs $8,499 to $21,650 installed. From about $142 a month at 0% APR for 60 months, the whole price financed, on approved credit.
Why is SwiftPro’s Yelp rating lower than its Google rating?
Yelp is a small slice of our reviews, about one in twenty, and it filters hard. It’s our lowest score at 4.4, and we count it in our total anyway. Every platform’s number and the date it was read are on our reviews page.
Is SwiftPro licensed and insured?
Yes. Virginia Class A contractor license 2705192276, licensed and insured, BBB Accredited with an A rating. We’re a Trane Comfort Specialist, Carrier experts, a Rheem Pro Partner and a Mitsubishi Electric Diamond Contractor.
Can I pay for a new system monthly?
Yes, on approved credit. From about $148 a month at 0% APR for 60 months, the whole price financed, on approved credit. Longer plans lower the payment and cost more in total. Here’s how financing works.
Who is the best HVAC company in Herndon?
The one that shows you its license, its price and every review before it comes out, and knows whether your permit comes from the Town or the county. Run the four checks above on anyone, us included.
See your Herndon price
Run every check above on us. The license is 2705192276, the reviews are on our reviews page, and the Herndon prices are on our Herndon furnace and AC page. Then the HVAC estimator gives your house its own installed price in about two minutes, and you can book a visit from the same page.
Need a repair or a tune-up rather than a new system? Our HVAC service page has those prices. And if you’re choosing a company for another town, we’ve written the same guide for Reston, Sterling, Ashburn, Centreville, Alexandria, Arlington and Woodbridge.
Call (703) 997-9757 or book online.
SwiftPro Heating, Cooling & Plumbing is a heating, cooling and plumbing company based in Chantilly, about six miles from Herndon, serving Northern Virginia. We’re a Trane Comfort Specialist, Carrier experts, a Rheem Pro Partner and a Mitsubishi Electric Diamond Contractor. Family owned, BBB Accredited with an A rating, 24/7 emergency service, Virginia Class A contractor license 2705192276, and rated 5.0 stars across 1,132 reviews on Google, Angi, Yelp, the BBB and Facebook. Read the reviews, or meet the company.
