5 AC Installation Contractors in Londonderry, NH
Top-Rated AC Installation Contractors in Londonderry
Southern New Hampshire Plumbing and Heating
“256 five-star reviewers praise the company's same-day emergency response and transparent upfront pricing. Customers specifically mention technicians Chuck and…”
Tom's Mechanical Services llc
“Eight of twelve reviewers specifically praise the same-day or emergency response capability, with three customers documenting after-hours calls that received…”
All AC Installation Contractors (5 total)
AC Installation Costs in Londonderry
New central AC installation costs in Londonderry, by system type and brand.
| Service | Low | Average | High |
|---|---|---|---|
Window unit | $168 | $392 | $784 |
Ductless mini-split (single zone) | $2,240 | $5,040 | $8,960 |
Central AC replacement (existing ducts) | $3,920 | $7,280 | $13,440 |
Central AC new install (with ductwork) | $7,840 | $13,440 | $22,400 |
Carrier (residential) | $4,256 | $6,944 | $11,760 |
Trane (residential) | $5,600 | $9,856 | $15,232 |
Lennox (residential) | $3,920 | $7,280 | $13,440 |
Rheem (residential) | $3,584 | $6,160 | $10,080 |
Prices reflect continental metro averages compiled from published industry cost guides, contractor surveys, and regional labor data. Last updated: April 2026.
AC Installation in Londonderry, NH: What to Expect
Summers in Southern New Hampshire push into the low eighties withreal humidity, making air conditioning less a luxury and more a practical necessity for indoor comfort. Winters dip well below freezing, so heating absorbs most of the household energy budget, but the sticky summer stretches quickly reveal which homes lack adequate cooling. For residents searching AC Installation in Londonderry, the local market offers five contractors holding an average rating of 2.8 stars across 486 reviews, with just one providing around-the-clock emergency coverage.
Understanding the cost brackets helps homeowners budget accordingly. Window units range from $168 to $784, while a single-zone ductless mini-split runs $2,240 to $8,960, and central AC replacement using existing ductwork spans $3,920 to $13,440. Pricing reflects equipment specifications, labor complexity, and permit requirements, as New Hampshire mandates that HVAC contractors hold a valid Class A, Class B, or Class C license from the state Office of Professional Licensure and Certification before pulling local mechanical permits.
Reviewer feedback points toward two standout performers. Southern New Hampshire Plumbing and Heating earns consistent praise for same-day emergency response and transparent upfront pricing, with technicians Chuck and Justin mentioned repeatedly across 256 five-star reviews. Tom's Mechanical Services achieves a perfect rating with clients specifically documenting rapid after-hours assistance during urgent calls. These patterns in speed and communication appear to separate highly recommended contractors from the rest.