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Find Air conditioning pros in San Dimas

Avatar for Global Green Solutions
Global Green Solutions
5.0(
248
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 2005

Free estimates

Emergency services offered

"Very happy with the new installation, replacement, and repair services for heating and air conditioning! The technicians were courteous, well-informed, and on time. They promptly resolved the problem and provided comprehensive explanations. A truly professional and trustworthy crew. Strongly suggested!"
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+24

Response time3 days
9 neighbors recently requested a quote
Recommended by7%of homeowners
Avatar for Air-Tech Air Conditioning & Heating Inc
Air-Tech Air Conditioning & Heating Inc
4.5(
202
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 1988

Free estimates

Warranties offered

"The service I received from Air-Tech was above my expectations. Alex made the selection process effortless and the installation was fast and efficient. The folks with Air-Tech are real pros."
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+8

Response time5 hrs
39 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for MSP Heating and Air, LLC
MSP Heating and Air, LLC
4.9(
328
)

Serving San Dimas, CA and surrounding areas

Approved

Super Service Award Winner

In business since 2016

Free estimates

Emergency services offered

"This is the 4th of July weekend and our air conditioning went out!! We appreciated the quick response and the quality of the work performed by Danny. He was very thorough and quickly resolved the problem. He was very courteous and professional."
duct job all R-8 ducting
4 Ton GOODMAN Furnace
customer Vlastos
duct job all R-8 ducting
furnace install

+67

Response time4 hrs
16 neighbors recently requested a quote
Recommended by94%of homeowners
Avatar for Temp Air System, Inc.
Temp Air System, Inc.
4.8(
59
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 2002

Free estimates

Credit card accepted

"We had Temp Air install our AC unit. The best decision we ever made. They were fast, reliable and dependable. Excellent customer service, did a phenomenal job. After a couple of years something was going on with our unit, I called them and immediately they send out a technician Juan, who was phenomenal. He explained what the issue was and resolved it asap! Highly recommend this company!"
Mini Split Installation
Mini Split Installation
Mini Split Installation
Mini Split Installation
Mini Split Installation

+14

Response time10 hrs
Response rate99%
7 neighbors recently requested a quote
Avatar for Trabuco Air
Trabuco Air
4.6(
130
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 1996

Free estimates

Emergency services offered

"Short notice call and he made arrangements to come see us with our air condition issue. Very cordial. Mask on as soon as he entered the door and explained everything in detail what he was going to do. Thank you so much! Nice and cold in the house again."
Response time5 hrs
Recommended by94%of homeowners
Avatar for McLay Services
McLay Services
4.8(
281
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 1978

Free estimates

Emergency services offered

"I had a great experience with your team. They serviced and repaired my mini-split and central They serviced my A/C systems, added refrigerant, and made sure everything was working properly before leaving. Mike was thorough, professional, knowledgeable, and did quality work. I highly recommend this company."
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+3

32 neighbors recently requested a quote
Recommended by93%of homeowners
Avatar for RS Air Conditioning & Heating
RS Air Conditioning & Heating
4.9(
23
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 1990

Free estimates

Emergency services offered

"I am so pleased with Ray and his work. The floor furnace is back in working condition, better than ever, especially when other's said it could not be fixed. Basically wanting to up sale rather than repair. Ray is very knowledgeable and knows what he is doing. Thank you Ray!"
New Outdoor Install
Furnace Install
Satisfied Client
Energy saver!
Carrier Water Soure

+2

Response time3 hrs
Response rate100%
Recommended by100%of homeowners
Avatar for Active Air Specialist Inc.
Active Air Specialist Inc.
5.0(
9
)

Serving San Dimas, CA and surrounding areas

Approved

In business since 2012

Free estimates

Credit card accepted

"The team that came out to replace our home ducting was awesome! They were friendly and knowledgeable. They left everything neat and clean. Would defiantly recommend!"
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+7

5 neighbors recently requested a quote
Recommended by44%of homeowners
Avatar for All City Plumbing, Air & Electrical
All City Plumbing, Air & Electrical
4.9(
271
)

Serving San Dimas, CA and surrounding areas

Approved

Super Service Award Winner

In business since 2009

Emergency services offered

Warranties offered

"Tyler Jones from All City Plumbing Air and Electrical did a great job replacing a gas valve in our garage. He was friendly and easy to engage with, clearly knowledgeable, and took the time to explain what he was doing. The work was completed efficiently and effectively, and everything was handled professionally from start to finish. I’d definitely recommend Tyler and All City for plumbing and gas-related work."
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+42

13 neighbors recently requested a quote
Recommended by97%of homeowners
Avatar for Penguin Heating and Air Inc
Penguin Heating and Air Inc
5.0(
15
)

Serving San Dimas, CA and surrounding areas

Approved

Super Service Award Winner

In business since 2025

Free estimates

Emergency services offered

"I highly recommend this company. Penguin heating & Air was very quick to respond to my request, fast text reply, sent them pics, they replied with a quote, which was way lower than anyone else on this site, or even our regular guy that we normally use, we scheduled an appointment for the very next day, which was today, he also finished the job the same day! David did a very good job, very professional. Despite a terrible rainy day, he got the job done. When he was done he walked me through with exactly what he did. He also quoted me for a service on an existing unit and his quote was almost $200 less than what our regular guy charges us... We will absolutely be using this company again."
Diamond Bar
Diamond Bar
Diamond Bar
Furnace Install
AC Condenser

+6

Response time2 hrs
Response rate100%
26 neighbors recently requested a quote
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FAQs for air conditioning projects in San Dimas, CA

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 San Dimas, CA homeowners’ guide to air conditioning services

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