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Products & Services

HVAC Systems
air conditioning contractors
air conditioning systems
central air conditioning
ductless air conditioning
gas furnace
geothermal heating and cooling
heating and cooling systems
high-efficiency furnace
home heating systems
HVAC companies
hydronic heating systems
air conditioning installation
air conditioning repair

Crawl Space Insulation

Home Energy Saving & Audit
energy efficiency audit
energy saving devices
energy saving products
energy saving tips
home energy audit
home energy conservation


Home Insulation
attic insulation
blown in insulation
cellulose insulation
duct insulation
green insulation
insulation contractors
pipe insulation
reflective insulation
rigid foam insulation
roof insulation
wall insulation
window insulation

Water Heaters
gas water heaters
high-efficiency water heater
hot water heaters
indirect water heater
instant hot water heater
on demand hot water heaters
solar water heater
tankless water heaters
water heater installation
water heater replacement

Air Sealing
sealing air leaks
air duct leakage
air duct sealing
air leakage testing
door air seal
window air leakage

Radiant Barrier
radiant barrier insulation
radiant barrier cost
roof radiant barrier

ductwork repair
ductwork installation
ductwork cost
furnace ductwork
HVAC ductwork
Duct Cleaning

Dryer Vent Cleaning

Before and After Pictures from Mount Holly
Before and After Condenser Cleaning

Before and After Condenser Cleaning

Before After
Before and After Condenser Cleaning Before and After Condenser Cleaning

Cleaning the outside unit and removing the debris can help your AC system run more efficiently.

Company Awards
Best of Gaston 2020
GSM Services was incredibly honored to win multiple titles this year for the 2020 Best of Gaston Awards! Thank you... [Read more]
Top Place to work Charlotte 2019
GSM was voted as one of the top places to work in 2019 by the Charlotte Observer.... [Read more]
Best of Gaston 2019
We won Best of Gaston 2019 for Best Heating & Air Conditioning Company and also Best Home Repair Company by... [Read more]
More Awards

Mount Holly's Reliable Insulation, Heating & Air Conditioning Repair Pros

We appreciate your good quality work.  We are well satisfied....
Happy Customers Surrounding Mount Holly, NC
Work Requests

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Reviews From Mount Holly
Testimonials From Mount Holly
We couldn’t be happier with all aspects of your company! Thank you ever so much!
Testimonial by The Browns from Mt. Holly, NC
Your two technicians who did the installing were very hardworking, very knowledgeable and also courteous.
Testimonial by Ms. Stroupe from Mt. Holly, NC
We had a great experience with GSM.
Testimonial by Kris V. from Mt. Holly, NC

Fast & Affordable Heating Service Specialists in Mount Holly, NC

If your furnace won't turn on, if there's a leak, if the blower isn't working or if you want regularly scheduled maintenance, you are in the right place! GSM Services has a dedicated and devoted team of furnace service professionals with decades of combined experience. Our trained technicians can provide a prompt and thorough inspection of your unit to determine the problem and suggest the solution. Our furnace service team provides FREE written estimates for all potential furnace repairs so you will never be surprised by the bill. Also, we provide furnace service for all types and models, including natural gas, oil, electric and propane. Don’t hesitate to contact us today, call or click to schedule your furnace service appointment with GSM Services!

Benefits of regular furnace service:

  • Optimal home comfort
  • Reliable performance
  • Better furnace efficiency
  • Extended life
  • Lower repair costs & increased energy savings

Proven Furnace Installation Experts

If your furnace is old or your bills seem too high, replacing your furnace will be the best option. Basic usage compromises your unit over time and keeping a damaged or old furnace may be costing you more money than installing a new unit. Our certified and highly trained team of furnace installation professionals can provide a thorough inspection of your unit to help you make that decision. Our skilled experts can replace all types of units with high-quality and energy efficient models that are guaranteed to lower your energy bills by as much as 30%. Trust our furnace installation professionals to provide you with reliable services every step of the way. Call or click today to schedule your FREE furnace installation estimate!

We install a variety of types of furnaces:

  • Gas furnaces
  • Oil furnaces
  • Electric furnaces
  • Propane furnaces
  • Heat pump systems

Mount Holly's Dependable Home Insulation Professionals

We specialize in a variety of home insulation services that are aimed to lessen your home's carbon footprint and save energy and money each month! We offer it all, from air sealing to ductwork to various types of insulation services such as blown in fiberglass, cellulose, injection foam, and more in Mount Holly, NC. We understand that you need to use the correct type of insulation in your home, and it needs to be placed in the correct areas.

Before we perform any insulation work in your home, we first take the time to conduct a custom home energy audit.  The audit is used to figure out what the root cause of your energy woes, and gives us an idea of what the best method would be to fix it.  At GSM Services, we not only test and investigate your home's energy usage, but we will discuss and prioritize the proper repairs. You'll know which ones will save you the most energy and why. This will also help direct you in making the best decision for you and your family.

Types of Insulation
  • Blown-in Fiberglass
  • Blown-in Cellulose       
  • Rigid Foam
  • Injection Foam
  • Radiant Barrier  
  • Sealing Air Leaks
  • Air Duct Sealing            
Areas of Home
  • Attic Insulation
  • Basement Insulation
  • Crawl Space Insulation
  • Garage Insulation
  • Wall Insulation
  • Floor Insulation
  • Ductwork Insulation

Crawl Space Insulation Experts

Is there moisture in your crawl space? Does your home have proper crawl space insulation? Even if you think your crawl space has enough insulation do not hesitate to contact us. We have a team of crawl space moisture and insulation experts that will give you peace of mind when it comes to your crawl space. It is always better to have too much insulation than to have a space without any insulation at all. Crawl space insulation is very important to the efficiency of your entire home due to the fact that moisture in your crawl space can also lead to rot, structural issues, and health concerns. Don't let moisture in your crawl space plague your home. Contact us today to learn more about our crawl space moisture solutions!

Air Conditioning Repair, Installation, & Service Company

Here at GSM Services, our skilled technicians can inspect your air conditioning system and provide the right services to prolong the life of your cooling system and keep your home comfortable. We provide repair and maintenance services for all brands and models of central and ductless air conditioners.

Our Air Conditioning Services Include:

  • Air conditioning tune-ups & maintenance
  • Air conditioning repair
  • Air conditioning system replacement
  • Refrigerant replacement
  • Thermostat repair & replacement
  • Ductless air conditioning
  • Central air conditioning

Comprehensive Home Energy Audits

Our team of home energy take the time to carefully examine your home and can provide comprehensive home energy audits that identify the areas that need improvement. Once we finalize the test, we will sit with you and show you exactly what was found and giving you a prioritized list of list of home energy tasks. Our custom home energy audits allow us to help homeowners improve the overall energy efficiency of their home's and can help save you money!

Evaluations Include:
  • Air Leak Inspection 
  • Thermal Scanning
  • Detailed Explanation    

  • Blower Door (Infiltrometer) Test
  • Insulation Level Check
  • Appliance & Lighting Checks
Job Stories From Mount Holly, NC
New Installation Multiple Furnace Systems - Local Church

From residential to light commercial our residential heating and cooling division will help keep your home or business comfortable.  We recently completed a 5 unit furnace installation at a local Church in Mount Holly, NC. 


Give GSM a call for a free estimate for new installations on heating and cooling systems for light commercial and residential homes.

New Installation Multiple Furnace Systems - Local Church - Photo 1New Installation Multiple Furnace Systems - Local Church - Photo 2New Installation Multiple Furnace Systems - Local Church - Photo 3
Work Requests From Mount Holly, NC
Project Location: Mount Holly, NC
Dryer isn't drying well, but it gets hot. Thinking I may need to have the dryer vent cleaned. Thanks! Additional information: Date requested: 09/08/2021
Project Location: Mount Holly, NC
We would like to start having regular cleaning and maintenance.
Project Location: Mount Holly, NC
Looking for maintenance contract for bi annual service to ensure HVAC runs smoothly. Additional information: Date requested: 06/10/2020
Project Location: Mount Holly, NC
1. Regular service - need filter replaced in my AC unit. I would like to set up the ESA for tune-ups in spring/summer and fall/winter for 2020. Service tech will require a ladder as my unit is in my attic. 2. AC is struggling to cool the past few days. Would like it inspected as part of regular service. Would like to set up inspection for Monday 6/8 in the afternoon or Wednesday 6/10 in the morning. Additional information: Date requested: 06/08/2020
Project Location: Mount Holly, NC
Summer tune up
Project Location: Mount Holly, NC
Would like to get a quote for replacing a 5 ton heat pump at our shop facility.
Project Location: Mount Holly, NC
Project Location: Mount Holly, NC
I need a air conditioner for our half basement
Project Location: Mount Holly, NC
Air-conditioning fan on outside unit will turn on but no air is coming through vents inside the house
Project Location: Mount Holly, NC
Two units upstairs aren't cooling
Project Location: Mount Holly, NC
Need new equipment for HVAC on main level of home
Project Location: Mount Holly, NC
I need someone to come and service my Mitsubishi outside unit. I believe there might be a leak.
Project Location: Mount Holly, NC
Would like estimate on replacing existing AC
Project Location: Mount Holly, NC
Heat pump is functioning but makes a lot of noise that's audible from inside the wall. Does not make noise when just the fan is running. Additional information: Date requested: 03/14/2019
Project Location: Mount Holly, NC
Interested in a quote for a whole house standby generator.
Project Location: Mount Holly, NC
Looking at replacement HVAC system
Project Location: Mount Holly, NC
Need the furnace replaced for the bonus room over the garage. The a/c part of the unit still works. thanks!
Project Location: Mount Holly, NC
Need quote for new HVAC. Current system won't cool when outside temp is above 80.
Project Location: Mount Holly, NC
My AC unit iced over. Additional information: Date requested: 06/25/2018
Project Location: Mount Holly, NC
Bonus room surrounded by attic space. Room temp climbs to upper 70's when outside temp gets to upper 80's. Air temp coming out of vents is 58-59 at night but climbs to 68-70 once outside temp gets to upper 80's. Concerned about duct leakage and general temp and ventilation of attic.