AC Installation & Replacement in Gaithersburg, MD
Replacing an air conditioner is one of the bigger investments you'll make in your home, and getting it right starts long before the equipment arrives. P&Y Heating and Cooling designs each Gaithersburg installation around a proper load calculation, your ductwork, and your comfort goals — not a one-size-fits-all box.
We handle the whole project: Manual J sizing, equipment selection, permits and inspection coordination with Montgomery County, professional installation, startup testing, and haul-away of the old system. You get a written quote with the equipment capacity, efficiency rating, and warranty spelled out clearly.
Signs It's Time to Replace Your AC
Replacement makes sense when repairs stop being worth it. Consider a new system if you're seeing several of these:
- Your system is 12–15+ years old and needs a major repair
- It still uses phased-out R-22 refrigerant, which is costly to service
- Energy bills keep climbing even after tune-ups and repairs
- Some rooms never cool while others get too cold
- The house feels humid and sticky even when the AC is running
- Frequent breakdowns and rising repair costs each season
Our AC Installation Process
A good install is 20% equipment and 80% workmanship. Here's how we protect your investment:
In-home assessment & Manual J
We measure your home, evaluate ductwork and insulation, and run an ACCA Manual J load calculation so the new system is sized to your actual home — not just matched to the old unit's tonnage.
Written equipment proposal
You get clear options across efficiency levels (SEER2), with pricing, warranty terms, financing, and any rebate eligibility laid out side by side.
Permitted professional install
We pull the Montgomery County mechanical permit, set the new equipment, make the electrical and refrigerant connections to code, and correct any airflow or drainage issues.
Startup, testing & walkthrough
We commission the system, verify refrigerant charge and airflow, confirm the temperature split, register your warranty, and show you how to run the thermostat.
Why Right-Sizing Matters More Than Brand
An oversized air conditioner cools quickly but shuts off before it removes humidity, leaving your home cold and clammy — a common problem in Gaithersburg's humid summers. An undersized one runs constantly and wears out early. That's why we start every replacement with a Manual J load calculation instead of just matching the old unit.
Proper sizing, correct refrigerant charge, and sealed ductwork have a bigger impact on comfort and efficiency than the badge on the equipment. We install quality, reliable systems and back the workmanship that makes them perform.
Financing & Rebates
A new system shouldn't wreck your budget. We offer financing options so you can spread the cost, and we'll walk you through Maryland energy-efficiency rebates and manufacturer promotions you may qualify for when you upgrade to a high-efficiency system.
What Affects AC Installation Cost
Local AC replacement generally runs $5,000–$14,000, with full-system replacements typically $7,000–$14,000. A 2–3 ton install using existing ductwork averages around $5,655. Your quote depends on:
- System size (tonnage) required by the Manual J load calculation
- Efficiency level — higher SEER2 systems cost more upfront but lower operating costs
- Whether ductwork needs repair, resizing, or sealing
- Straight AC vs. a matched heat-pump or dual-fuel system
- Electrical upgrades, line-set replacement, and permit fees
- Financing terms and any available Maryland energy rebates
Request Service
Fast response · No obligation · Upfront pricing
Why P&Y for Your AC Installation
A new system is only as good as the install behind it. Here's how we protect your investment.
Manual J, not guesswork
We size every system to your home's actual cooling load — square footage, windows, insulation, and ductwork — so you get even comfort and proper dehumidification, not an oversized unit that short-cycles.
We handle the permit
Montgomery County requires a mechanical permit for AC replacement. We pull it, do the work to code, and coordinate the inspection so you don't have to.
Financing and rebate guidance
We offer financing and walk you through Maryland energy rebates and manufacturer promotions you may qualify for on a high-efficiency system.
Where We Provide AC Installation & Replacement
We install and replace air conditioners across Montgomery County, from high-efficiency upgrades in North Potomac to end-of-life builder-system replacements in Germantown. Every install includes a load calculation and county permit coordination.
We serve ac installation & replacement across Gaithersburg and all of Montgomery County, including:
AC Installation & Replacement FAQs
How long does a new AC installation take?
Should I replace my furnace at the same time as my AC?
How much does it cost to install a new AC in Gaithersburg?
Do I need a permit to replace my air conditioner?
What SEER rating should I choose?
Trusted by Your Neighbors
P&Y (Pedro) and his crew were absolutely outstanding. My unit was about 20 years old and giving problems. He was very responsive and made an appointment the same day. He not only told me the issue but gave me options — a repair price and a price on a new unit — even knowing the unit was 20 years old. Other companies just told me to change the unit. His crew spent almost 7 hours and tested it so it worked perfectly. Reasonable and great pricing than these big box companies.
Sandeep Visveswaran
Verified Google review
AC Installation
10/10 recommend! As new homeowners, we truly appreciated how professional, knowledgeable, and patient the entire team was. They clearly explained the work and taught us how to properly use and maintain our new HVAC system. When we later had an issue with the ducts, they kindly returned, identified the problem, and saved us a significant amount of money.
Silvia Garcia
Verified Google review
Heating System Installation
I contracted with P&Y to replace my HVAC system — furnace, evaporator and condenser/compressor unit. They were on time, clean and professional. Price and warranty were the best I found; 5 previous estimates were significantly higher. I highly recommend P&Y!
Gene Verzi
Verified Google review
HVAC Replacement
Need AC Installation & Replacement in Gaithersburg?
Family-owned, licensed, and available 24/7. Call now for fast service and a free estimate across Montgomery County.
- 5.0★ (112+ reviews)
- Licensed & Insured
- 24/7 Emergency Service