Replacing a cooling system at the end of its life, sized for 5,003 feet

AC Replacement in Fort Collins, CO

An air conditioner in Fort Collins lasts 15 to 20 years. When yours reaches that age and the repairs start coming every season — or one repair costs a large fraction of a new system — signs you need a new AC installationment stops being a question of if and becomes a question of when and what. The decision is worth doing properly: a new system sized at altitude, matched to your ductwork, and commissioned with its charge and airflow actually measured will cool better and cost less to run than the unit it replaces. DNA Refrigeration Heating & Cooling replaces central AC across Fort Collins. Call (970) 932-2324 any time.

AC replacement in Fort Collins: new high-efficiency air conditioning condenser installed at a home
Sized at altitude. Commissioned with readings, not guesses.
About this service

What AC replacement in Fort Collins really involves

Replacement is not a swap. It is a new load calculation, a ductwork assessment, a permit, a new line set and drain, and a commissioning visit that records charge and airflow. The old unit's tonnage is a starting point, not an answer — houses change, insulation improves, and the old system may have been wrong from the start.

The Fort Collins numbers frame the decision. Nationally, AC replacement ran $3,887–$8,073, averaging $5,978, in October 2026 (Angi, national figures), and a full 3-ton split system in Fort Collins was modelled at $8,550–$14,380 the same month (NumeralQ, modelled, not a contractor bid). Those are different scopes — the national figure is a marketplace average including low-cost markets, the Fort Collins figure is modelled from material prices and local labour — and your quote will depend on tonnage, efficiency, ductwork and the permit. What matters is the comparison: a compressor or coil repair on a 17-year-old system, repeated, quickly costs more than the remaining life it buys. At 5,003 feet the new system also needs to be sized for altitude — roughly 10–20% capacity loss versus sea-level ratings — and for dry air, where sensible cooling dominates and the design wet bulb is only about 60°F. A mechanical permit is required, filed through the Accela Citizen Portal, and permits are valid for 180 days.

  • ✓ Repair-versus-replace with real numbers
  • ✓ New Manual J sizing at altitude
  • ✓ Ductwork assessed, not assumed
  • ✓ Mechanical permit included in the job
What's included

What our AC replacement service includes

A replacement should leave you with a system that holds setpoint on a 93°F afternoon, runs quietly, and costs less to run than the one it replaced. Here is what goes into that.

01
✓

Repair-versus-replace, honestly

We compare the repair cost against the system's age and remaining life, and against the dated cost ranges above. If a repair is the better call, we say so — a replaced system that did not need replacing is a failure, not a sale.

02
✓

Manual J sizing at altitude

The new system is sized from a room-by-room load calculation at 5,003 feet, not from the old unit's nameplate. Oversizing is as costly as undersizing in a dry climate: short cycles, poor comfort and worn components.

03
✓

Ductwork assessment

We check whether the existing ducts can support modern high-efficiency equipment. In many pre-1990 Fort Collins homes the answer is no without work — undersized returns and leaky runs that a new unit cannot fix on its own. Duct sealing or repair is quoted as part of the job where it is needed.

04
✓

New line set, drain and electrical

A contaminated line set or a sagging drain is how new systems develop old problems. Replacement includes a new line set, a correctly pitched condensate drain with a float switch, and verified electrical connections.

05
✓

Efficiency tier explained plainly

We explain what each SEER2 tier actually buys in a dry, high-altitude climate, and what it does not — including the fact that no central-AC-only rebate was found under Efficiency Works in November 2026 research, so efficiency is a running-cost decision, not a rebate decision.

06
✓

Commissioning and inspection

After installation we charge by weight and verify by superheat and subcooling, measure airflow and temperature split, and confirm the system holds setpoint. The final mechanical inspection is scheduled and the readings are left with you.

How it works

How our ac replacement process works

Call (970) 932-2324 any time. Tell us the system's age, what has failed, and what it has cost you lately. We will ask the questions that show whether replacement is even the right conversation.

We measure the home, inspect the ductwork, check the electrical supply and look at outdoor unit placement, including any HOA or historic-district visibility considerations.

You get a written quote with the equipment, ductwork scope, permit and commissioning included, and the efficiency tiers compared honestly. The dated national and Fort Collins ranges above are the context, not the quote.

A mechanical permit is filed through the Accela Citizen Portal. Installation covers the indoor and outdoor units, line set, drain, electrical connections and thermostat, with the old equipment removed and the work area left clean.

We charge, test and document the system, walk you through the thermostat and filter schedule, and confirm the final mechanical inspection. The system is handed over with its numbers recorded, not just running.

STEP 01Call and talk through the system

Call (970) 932-2324 any time. Tell us the system's age, what has failed, and what it has cost you lately. We will ask the questions that show whether replacement is even the right conversation.

Tools & methods

Tools and methods we use on every job

01
✓

Manual J software

Room-by-room load calculation at altitude, so the replacement matches the house instead of the old unit's nameplate.

02
✓

Duct design and leakage testing

Duct capacity measured so a new high-efficiency unit is not strangled by 30-year-old ductwork.

03
✓

Refrigerant scales and gauges

Charge weighed to specification and verified by superheat and subcooling readings.

04
✓

Vacuum pump and micron gauge

A deep vacuum with a measured micron reading before charging, so moisture and air never enter the new system.

05
✓

Airflow measurement

Supply and return airflow checked against the equipment's rated range — the step that catches undersized returns in older homes.

06
✓

Electrical testing

Supply, disconnect and thermostat wiring verified safe and correct before handover.

Real results

AC replacement, home by home in Fort Collins

Fort Collins homes

Second replacement in a Southridge two-storey

Southridge's 1985–1993 homes are now on their second or third cooling system, and the replacements fitted in the 2000s are themselves reaching the end of their life. The story here is replacement quality: oversized units from the last round, duct leakage in 35-year-old ductwork, and mature-tree debris in the condenser.

What good work addresses: a fresh load calculation instead of copying the last unit's tonnage, a duct assessment before the new equipment is chosen, and commissioning readings that prove the new system performs as specified.

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Fort Collins homes

First replacement in a Rigden Farm home

Rigden Farm's master-planned homes were built between 2000 and 2011, and that cohort is hitting its first furnace and AC replacement wave together. The original builder-grade equipment is at the end of its life, and the complaint is usually the upstairs: it will not cool, and the system runs constantly trying.

What good work addresses: checking whether the original ductwork can support modern equipment, sizing at altitude, and addressing the upstairs imbalance with balancing or zoning rather than simply fitting a bigger box.

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Fort Collins homes

Replacing a swamp cooler and a dead AC in Old Town

Old Town's pre-1930 homes often carry a mix: a window unit here, an evaporative cooler there, a central system added decades ago and now dead. The median single-family home in Old Town was built in 1927, and none of them were built for central cooling.

What good work addresses: a survey that treats the house as it is — thin walls, retrofitted ducts, tight basements — and a replacement plan that may combine ducted cooling downstairs with a ductless head upstairs, with exterior placement handled as a visibility question under the voluntary Old Town guidelines.

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Problems we solve

AC replacement questions we answer every week

Replacement is a big decision with a long tail. These are the questions Fort Collins homeowners ask before they commit.

Ask a pro →
01

How long does an AC last in Fort Collins?

15–20 years (Balance Point, November 2026 research). Altitude derating, hard cycling on hot afternoons and neglected maintenance pull toward the short end; correct sizing, annual maintenance and clean ducts push toward the long end.

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02

When should I repair my AC versus replace it?

Repair usually makes sense under about 12–15 years with a single-component fault. Replacement is worth a serious look at 15–20 years, with a major repair such as a compressor or coil, or when repairs keep coming every season. The one-third rule used locally — a repair above roughly a third of a new system's price on a 15-plus-year unit — is a reasonable starting point, not a law.

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03

What does AC replacement cost in Fort Collins?

Nationally $3,887–$8,073, averaging $5,978, in October 2026 (Angi). A full 3-ton split system in Fort Collins was modelled at $8,550–$14,380 the same month (NumeralQ, modelled, not a contractor bid). Your quote depends on tonnage, efficiency, ductwork and the permit — which is why it follows a survey, not a phone guess. Figures checked November 2026.

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04

Will a new AC cool my upstairs?

Only if the ducts and sizing are right. A bigger unit on undersized ducts just short-cycles. We measure airflow and duct capacity as part of the quote, and where balancing alone cannot fix the upstairs we discuss zoning or a ductless head for the upper floor.

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Proof you can check

How HVAC licensing works in Fort Collins

  • HVAC work in Fort Collins is licensed by the City of Fort Collins, not the state — Colorado licenses only electricians and plumbers at state level. Fort Collins licenses HVAC contractors through the City — ask us for our licence details when you call.
  • Refrigerant handling follows EPA Section 608 rules as a general industry requirement.
  • 5.0 ★ (23 Google reviews) — all 23 reviews are 5-star.
  • Open 24 hours · 7 days a week — 2757 Sternwheeler Dr, Fort Collins, CO 80524.
Customer reviews

What Fort Collins homeowners say

★★★★★
“Fantastic business! Dennis is amazing, fixes, replaces, installs and knows everything about his profession. He under cut another competitor by $5800 and never exaggerates work that doesn't need doing. Very trustworthy, and very much appreciated. I have another whole AC unit that will need replacing soon, and I know who I'm going to for the job. Thanks!”
JH

James HadleyGoogle review · 5 months ago

★★★★★
“We had a great experience working with this company. From the beginning, they have been incredibly open and helpful. They took the time to explain everything clearly, answer our questions, and genuinely work with us rather than simply trying to sell us a service. We really appreciate the effort they put into helping us find the best option for our situation. Highly recommend!!”
HC

Hannah ClarkGoogle review · a month ago

Good questions

Questions Fort Collins homeowners ask about AC replacement

(970) 932-2324 →

15–20 years (Balance Point, November 2026 research). Systems that were oversized at installation, never maintained, or run on leaky ductwork die young; systems sized at altitude, maintained annually and fed by sound ducts last toward the top of the range.

When the system is 15–20 years old and facing a major repair, or when repairs recur every season, replacement usually costs less over the next five years than keeping the old unit alive. A single-component repair on a younger system is almost always the better call. We show you both numbers before you decide.

Nationally, $3,887–$8,073, averaging $5,978 (Angi, 22 October 2026). A full 3-ton split system in Fort Collins was modelled at $8,550–$14,380 (NumeralQ, October 2026, modelled, not a contractor bid). Those are different scopes; your written quote follows a survey of your house, its ducts and the permit.

Yes. AC replacement triggers a mechanical permit in Fort Collins, applied for through the Accela Citizen Portal, with rough-mechanical and final inspections. Permits are valid for 180 days. Permit fees were not verified at the time of writing (November 2026), so no fee figure is published here.

Ready when you are

Is it time to replace your AC? Call (970) 932-2324

Tell us the system's age and what it has cost you lately. We will survey the house, size the replacement at altitude, and quote it in writing — and tell you straight if a repair is the better call. Open 24 hours, 7 days a week.

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Call to book

Get in Touch

Call (970) 932-2324 any time, day or night. We are open 24 hours, 7 days a week, from 2757 Sternwheeler Dr, Fort Collins, CO 80524. Phone is the way to reach us — there is no email address for the business, so call any time, day or night — we are open 24 hours, 7 days a week.

Call anytime(970) 932-2324
Office hoursOpen 24 hours · 7 days a week
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