How much does an AC replacement cost in Merrimack, NH?
US national rangeUpdated Prices checked October 20262 sources
An AC replacement costs $3,887 to $8,073 nationally, typical $5,978. We have no documented price index for Merrimack for this job, so this is the US national range from HomeAdvisor, checked October 2026.
US national range, not adjusted for this city
- Low
- $3,887
- Typical
- $5,978
- High
- $8,073
AC replacement cost in Merrimack, NH
We have no documented price index for Merrimack for this job, so the table shows the US national range.
| Estimate | Low | Typical | High | Basis | Checked |
|---|---|---|---|---|---|
| US national range | $3,887 | $5,978 | $8,073 | Per system, installed (unit plus labor); typical range of customer-reported jobs (HomeAdvisor) | October 2026 |
AC replacement cost by type or size
US national figures in USD, as published by each source.
| Type or size | Price (USD) | Source |
|---|---|---|
| 3-ton central AC replacement, existing ducts | $5,500 to $10,000 | Fixr |
| 3-ton central AC replacement with new ducts | $7,500 to $16,000 | Fixr |
What drives the cost of an AC replacement
System size
Capacity in tons depends on home size, climate, sun exposure and insulation.
Efficiency (SEER2)
Higher-efficiency units cost more up front and less to run.
Ductwork
New ductwork is the largest add-on, at $1,000 to $5,000.
System type
Split, packaged, heat pump and ductless systems are priced differently.
Electrical and drain work
A panel upgrade or new condensate line adds cost.
Labor
Installation typically takes four to eight hours, about $300 to $1,600 in labor.
Permits and what's included in Merrimack
Permit note
A mechanical or electrical permit and an inspection are usually required. Ask whether the quote includes them.
Rules are set locally; confirm with Merrimack’s building department.
What’s usually included
- The new outdoor and indoor equipment
- Refrigerant lines, electrical connection and startup
- Removal of the old unit (confirm on the quote)
Scopes vary. Get the scope in writing on every quote.
Get AC replacement quotes in Merrimack
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Top-ranked HVAC contractors in Merrimack
The top 3 of 526 HVAC contractors we rank for Merrimack, NH, by CR Score. Paid placement never changes rank.
- #1Heritage Home ServiceCR Score 654.8from 7,956 Google reviews
- #2High Ground Service Pros - Plumbers Electricians & HVAC TechniciansCR Score 644.9from 2,303 Google reviews
- #3Sanford Temperature ControlCR Score 644.9from 1,832 Google reviews
AC replacement cost in Merrimack: questions
How much does an AC replacement cost in Merrimack, NH?
Do I need a permit for an AC replacement in Merrimack?
What affects the cost of an AC replacement?
How many HVAC contractors serve Merrimack?
What is usually included in the price?
Sources
Checked October 2026. Figures are estimates, not quotes.
- HomeAdvisor: AC unit installation cost · page updated June 17, 2026 · checked October 2026Primary source. Used for: Low, typical and high; ductwork, labor and efficiency drivers.
- Fixr: Central air conditioner installation cost · page updated August 29, 2025 · checked October 2026Used for: 3-ton replacement ranges with and without new ducts; drivers; permit.
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