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Find Air conditioning pros in Waltham

Avatar for Airco Home Comfort Services LLC
Airco Home Comfort Services LLC
4.7(
33
)
Central A/C - Install - For BusinessCentral A/C - Service or RepairCentral A/C - Service or Repair - For Business+11 more

Serving Waltham, MA and surrounding areas

Approved

In business since 1998

Free estimates

Warranties offered

"I whole heartedly recommend Airco. Their team was experienced, skillful, friendly and professional throughout the duration of this job, from Joe's first visit to my home to discuss air conditioning options to Derek and Cam's final touches on the duct system. I had complete confidence in them, as well as in Steve, Danny, Frank and Patrick. Additionally, Airco's connections to MassSave and Commerce Bank meant financing and payment options to suit my budget. No more hauling loud and heavy window a.c. units up from the basement. Instead, I am enjoying consistent cooling throughout my home with no noise whatsoever. I am a very happy customer!"
Additional Photos
Additional Photos
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Additional Photos

+4

Response time2 days
1 neighbors recently requested a quote
Recommended by96%of homeowners
Avatar for Genove Oil & Air Co
Genove Oil & Air Co
4.7(
217
)
Central A/C - InstallCentral A/C - Install - For BusinessCentral A/C - Service or Repair+12 more

Serving Waltham, MA and surrounding areas

Approved

In business since 1977

Free estimates

Emergency services offered

"We have been in our home for a little over a year and thought it best to have our furnace serviced especially since we don't have a detailed history of service. Frankie D showed up 5 minutes early for our appointment which was fantastic. Frankie was quick, clean and gave me a once over on the age and condition of our furnace. We talked about when the next service would be due. I couldn't have asked for a better experience and I am thankful that we now have our go to company for anything furnace related."
Additional Photos
Additional Photos
Additional Photos
Pics
Pics

+2

Response time12 hrs
Response rate100%
14 neighbors recently requested a quote
Avatar for Ace Hardware Home Services
Ace Hardware Home Services
4.5(
53
)
Central A/C - InstallCentral A/C - Install - For BusinessCentral A/C - Service or Repair+12 more

Serving Waltham, MA and surrounding areas

Approved (Corporate)

In business since 1967

Free estimates

Emergency services offered

"Our daughter and her husband are living out of the country, temporarily. When their leasees said the furnace was blowing cold air, we wanted the repair done quickly and at a good price. Unique Indoor Comfort Heating & Cooling responded right away and came to the property the same day we called. Very professional!"
Heat Pump
Mitsubishi Hyper Heat
Multiple Ductless Heat Pump Installation
Additional Photos
Additional Photos

+6

Response time1 day
Response rate100%
5 neighbors recently requested a quote
Avatar for Druziako HVAC Inc
Druziako HVAC Inc
4.7(
157
)
Central A/C - InstallDuctless Mini-split A/C - Install or ReplaceCentral Air Cleaner - Install or Replace+1 more

Serving Waltham, MA and surrounding areas

Approved

In business since 1990

Free estimates

Emergency services offered

"I’ve been a satisfied customer of Druziakos HVAC for 17 years, so when I found out I needed my gas furnace and central air replaced I didn’t look to anyone else. Everyone in the office was very helpful with the Mass Save program and process. They also submitted my rebate applications and helped with the warranty info. The work was done when scheduled and very quickly. The technicians were polite and answered all my questions."
Aprilaire Dehumidifier
Attic Air Handler
Duct Cleaning before and After
Attic Ductwork
Aprilaire Humidifier

+3

Response time11 hrs
15 neighbors recently requested a quote
Recommended by95%of homeowners
Avatar for Peter Paone HVAC
Peter Paone HVAC
4.9(
24
)
Central A/C - Service or RepairCentral Air Cleaner - Install or ReplaceCentral Air Cleaner - Repair or Service+3 more

Serving Waltham, MA and surrounding areas

Approved

In business since 2019

Free estimates

Small jobs welcome

"Peter did an excellent job tuning up my A/C system. He was extremely diligent in making sure my A/C unit was up to speed for cooling for the upcoming summer weather. I know I will most likely need a new system installed in the near future as this one is on it's last legs. I know who to call when I need a new A/C unit installed and it will be Peter!"
hvac
Ductwork
air conditioning
Mechanical
hvac

+1

Response time12 hrs
Response rate90%
1 neighbors recently requested a quote
Avatar for Emerald HVAC LLC
Emerald HVAC LLC
5.0(
15
)
Central A/C - Service or Repair

Serving Waltham, MA and surrounding areas

Approved

Super Service Award Winner

In business since 2024

Free estimates

Small jobs welcome

"My central AC unit has been broken for several years. intermittently working during hot summers. I've had several HVAC companies come to diagnose and all of them told me different things: replace the whole system, new lines, etc. potentially costing tens of thousands of dollars. So I decided to troubleshoot by myself and pinpointed the issue: the filter dryer needed to be replaced. No company wanted to do this small job. I called Emerald HVAC and told them about my issue, they sent in José, who diagnosed the issue to be what I said. He replaced the filter dryer and the AC unit works perfectly now after several years! In short, Emerald HVAC will be my first choice for any HVAC work in the future. They are honest, professional, and reasonably priced. I recommend them without reservation!"
Response time1 day
Response rate93%
27 neighbors recently requested a quote
Avatar for SumZero Energy Systems, LLC
SumZero Energy Systems, LLC
4.4(
23
)
Central A/C - InstallDuctless Mini-split A/C - Install or Replace

Serving Waltham, MA and surrounding areas

Approved

In business since 2009

Free estimates

Credit card accepted

"SumZero Energy Systems have been excellent in the last several months with supporting the replacement of my air conditioning system in my old condo as well as servicing my furnace. A price comparison with other local companies also prooved SumZero Energy Systems offered the best price. When I purchased a home a few months later, I called them to take a look at my air conditioning system and furnace because I felt as though they had provided such excellent service in the past. It was a no-brainer to ask for consultation regarding the heating and cooling systems in my new home! When I contacted them for assistance or consultation, they are usually quick to respond and provide appointment times had a very convenient window! They have shown up on time to all of the appointments I have had. David S. has always taken the time to explain everything thoroughly and answer all my questions. I highly recommend SumZero Energy Systems!"
Mitsubishi Heat Pump
MITSUbishi Hyper Heat Heat Pump
Wall Unit (GL Model)
'One-Way' Ceiling Cassette
'Floor Mount' Unit

+9

Response time2 days
Response rate88%
18 neighbors recently requested a quote
Chambers Heating & A.C. Service
4.5(
51
)
Central A/C - Service or RepairCentral Air Cleaner - Repair or ServiceCentral Humidifier - Repair or Service

Serving Waltham, MA and surrounding areas

Approved

In business since 1992

Free estimates

Emergency services offered

"I found Chambers Heating and AC thru Angie's list and Stephen reached out to me the same day. We set up an appointment and Kevin came out the very next day. Kevin showed up on time and fixed our issues right away. He was kind and professional. He also gave me some tips to keep my system in tip-top shape. The price was very fair and they have gained my business. I will hire them again for future repairs and maintenance."
93% High Efficiency Gas Furnace with AC
Baseboard Zone on a Steam Boiler
Supply Header with Circulators
Before Pic w/zone valves & Loose Wiring
Gas Fired tankless water heater

+6

1 neighbors recently requested a quote
Recommended by97%of homeowners
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FAQs for air conditioning projects in Waltham, MA

Most professional HVAC technicians require two to three hours to complete an expansion valve replacement. The timeframe depends on your unit's accessibility and whether additional repairs are needed. The process involves recovering refrigerant, removing the old valve, installing the new component, and recharging the system. Scheduling during less busy seasons may result in more convenient appointment times.

Operating your air conditioner with a malfunctioning expansion valve isn't advisable. Continuing to run the system could potentially damage other components, particularly your compressor, which is significantly more expensive to replace. If you notice performance issues like inconsistent cooling or unusual noises, it's best to have your system inspected before continuing regular use.

Expansion valves don't have a standard replacement schedule, as their longevity depends on system usage, maintenance frequency, and environmental factors. Regular professional maintenance helps identify potential valve issues before they cause system failure. Having your HVAC system serviced annually allows technicians to monitor component condition and recommend preventative replacements when necessary.

Refrigerant leaks require prompt professional attention. If your expansion valve is leaking, you'll likely notice reduced cooling performance and possibly hear hissing sounds near the unit. Addressing leaks quickly prevents further system inefficiency and avoids the environmental impact of released refrigerant. Your HVAC technician will need to repair the leak and recharge the system with the proper refrigerant type and amount.

Because many AC issues present similar symptoms, professional diagnosis is recommended. Problems like inadequate cooling, inconsistent temperatures, or strange noises could indicate expansion valve issues, but might also stem from refrigerant leaks, electrical problems, or airflow restrictions. A qualified HVAC technician has the tools and expertise to accurately identify the root cause and recommend appropriate repairs.

The Waltham, MA homeowners’ guide to air conditioning services

From average costs to expert advice, get all the answers you need to get your job done.