I've been using Diamond Air Services for over 5 years, and they've earned 5 stars every single time. They truly are a dream team! From routine maintenance to service calls, they've always been professional, honest, reliable, and incredibly knowledgeable. The technicians are punctual, friendly, and take the time to explain everything clearly. I never feel pressured into unnecessary repairs--they genuinely care about doing what's best for their customers. It's rare to find a company that consistently delivers outstanding service year after year, but Diamond Air Services does exactly that. I trust them completely with my HVAC needs and recommend them to anyone looking for dependable, high-quality service. Thank you for five years of exceptional work. You've earned a customer for life! read more

Oscar was absolutely fantastic! From the moment he arrived, he knew exactly what needed to be done and got straight to work. He was extremely knowledgeable and confident, and he was able to answer every question I had without hesitation. What really stood out to me was how efficient and professional he was. I never felt like I had to explain things multiple times or worry about whether the job was being handled correctly. He assessed the situation, explained what was needed, and took care of it without wasting any time. If you're looking for someone who knows what they're doing, communicates clearly, and takes pride in their work, I highly recommend Oscar. He made the entire experience easy and stress-free, and I would absolutely request him again. Great service from start to finish! read more

Diamond Air always comes through for me when I need them the most. Howie is awesome and very professional. I highly recommend Diamond Air!

First off i have to say Anthony did an awesome job! He was very pleasant, professional, knowledgeable, and easy to work with. He took the time to explain the issue with our A/C system and ensured everything was handled properly. I really appreciated his professionalism and friendly attitude throughout the service. Excellent service from start to finish. I highly recommend Diamond Air Services!!! read more

Excellent customer service. I had scheduled for a preventative maintenance for my AC. Technician was punctual and courteous and the job was completed without incident However, we had issues that evening with the AC. A service was scheduled next day and the issue was fixed promptly. Howie was prompt and efficient. I am happy with the service overall. read more

Diamond Air did a good job, at a reasonable and competitive price, installing a new AC/furnace system to replace our older system. When we encountered minor troubles after installation, they returned quickly, two times, to check the system and repair as needed. While the overall air conditioning is satisfactory, it appears that there is an issue with the house's old network of ducts. Diamond Air identified this and is scheduled to address it later. In summary, they worked with an existing situation, and they were responsive when problems were encountered. They demonstrated professionalism and willingness to identify and address issues as needed. read more

Quick response and great communication. Service was excellent! Air conditioner was repaired in less than a week from the initial visit. read more

DO NOT USE THIS COMPANY Had them come out multiple times, charged for things that didn't need to be done. Even had one technician tell me my system is a fire hazard and should not be used at all costs and needed immediate replacement. His own partner showed up a few days later and laughed and said no that's not the case and not sure why he would say that. These people are scammers, do not use them. read more

We have used and been impressed by the quality and service provided by Diamond Air for over 10 years. They really came through for us yet again when we were in a bind and needed an evaluation of our HVAC system ASAP. They saved us $10K!!! We are sold on their service and expertise-- and they are great people too. We will never use any other company read more

I selected Diamond Air Services as the contractor for my A/C system replacement. Oscar and Chris came to work on the project yesterday. They work very carefully and tried to minimize all impacts to our living. I like the company and the technicians, and like to recommend them to all other people who need a contractor for A/C system. read more

8/1/26Anthony is very professional, courteous, friendly and honest. His company installed a new Carrier AC and his crew had to endure 130 degree heat in the attic installing a new furnace and ducting which I and my wife greatly appreciated. He also gave us the best pricing of all the contractor bids. Can highly recommend the company for all your ac and heating needs. Dave K read more

This review is looong over due. Diamond Air is truly the 'ONLY' company you should be calling for HVAC services. They are quick to respond the quality of service, professionalism, and overall customer care is what won me over. Anthony gave us the best price on a new system a few years back. There were no hidden fees, additional costs, the installation process was non intrusive, and flawless! We definitely made the right choice in going with Diamond Air! *Bonus they really remember who you are! How cool () is that?!?! Team 'Diamond Air'! A Loyal San Dimas Customer read more

Prompt, thorough service. This is the second time we've had Diamond come out to do maintenance on our AC system. Mike checked everything carefully and did a great job explaining the health of the system and possible problems to look out for in the future. I highly recommend Diamond and will continue calling for HVAC needs in the future. read more

Sky was an outstanding technician sent by Diamond Air Services. He arrived quickly, diagnosed the issue efficiently, and was honest throughout the entire process. I really appreciated that he gave me several options to consider instead of pressuring me into one solution. What impressed me most was how clearly he explained everything. Since I know very little about how HVAC systems work, he broke it down in a way that was easy to understand, in the best way possible. He was patient, knowledgeable and incredibly skilled. Thank you, Diamond Air Services for sending someone with Sky's expertise and value to my home. He's a true asset to your team, and I highly recommend Diamond Air Services! read more

My air conditioner stopped cooling Friday night, and in a panic I contacted Diamond Air Services. They responded before any of the other companies I reached out to and were able to send a technician on Saturday. Mike came out and thoroughly evaluated my system (which is 20 years old). Even though there wasn't one obvious reason for the problem, he carefully checked every possibility. He found that the refrigerant was low and that the pressures weren't resetting as they should. He recharged the system, reconnected my electrostatic filter, and took the time to explain what might be causing the issue, as well as discuss possible future options. Mike was incredibly knowledgeable, professional, and personable. I felt confident in his assessment and appreciated that he never tried to pressure me into unnecessary repairs or a replacement. I feel very lucky that he was my technician. I highly recommend Diamond Air Services! read more

We are so happy with the new A/C unit we purchased last year. Howie recommended a great unit at a great price. The unit is sleek and isn't an eye sore in our backyard. The company is great at communicating and just came out to perform an annual maintenance. The technician was very professional, arrived on time, and explained in detail what he did. I highly recommend Diamond Air Services. read more

I cannot thank this company enough. Dealing with a leaking condenser coil is stressful, but they made the factory warranty replacement easy. Anthony was an absolute lifesaver, making sure our home stayed cool until the new part arrived. Jose and his crew did the actual replacement and were fast, polite, and professional. Outstanding service all around! read more

I had an excellent experience with Diamond Air Service. From scheduling to completion, the entire process was smooth and professional. The technician arrived on time, was very knowledgeable, and took the time to explain everything clearly. They carefully inspected my AC system, identified the issue, and fixed it efficiently without any pressure or unnecessary upselling. What stood out the most was their honesty, professionalism, and quality of work. My AC is now running much better and cooling efficiently again. It's hard to find a company you can truly trust, but Diamond Air Service exceeded my expectations. I highly recommend them to anyone looking for reliable and professional AC service! read more

My old HVAC unit was old and the electric bill was crazy high. I was looking for a replacement and received a couple estimates for different options and brands. Among the options, Anthony did offer a good price for CARRIER - 4.0 TON 18 SEER VARIABLE SPEED HEAT PUMP AND MULTI STAGE FURNACE. I did a research about this particular unit and decided to go with it rather than going with other brands like AC Pro and Daikin where they asked for about the same price. Anthony also matched the 12 years warranty offer like Daikin. 24 months payment with 0 interest was also another good deal. The crew Jose, Ethan and Oscar showed up on time and completed the installation in one and a half day. The old unit was removed and platform was inspected before putting the new one in place.they also installed a new breaker box for safety. The finished looks a lot nicer than my 20 years old unit. Overall I'm happy with the service and can't wait to seeing how it gets us in summer. read more

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I recently had a HVAC installed by Diamond Air Service, and I couldn't be happier with the experience. From start to finish, the entire team was professional, punctual, and respectful of our home. They worked efficiently, and kept everything clean throughout the installation process and their pricing was reasonable and transparent. Thank you, Anthony,Bobby and his crew and Edwin and Ethan. They all went above and beyond to ensure everything was done correctly and answered all of questions along the way. read more

I had a great experience with Diamond Air Servcies. Their pricing was fair and affordable compared to other quotes I received, and their communication throughout the project was excellent. They kept me informed every step of the way and completed the work exactly when they said they would. Their commitment to customer service throughout, and after the job was finished, was excellent. We experienced an issue shortly after the installation, and when I contacted them, they came out the very next day and resolved it without any hassle. It's refreshing to work with a company that stands behind its work and responds quickly when a customer needs assistance. I highly recommend them to anyone looking for a reliable, honest, and professional HVAC contractor. Their workmanship, communication, and customer service exceeded my expectations. read more

So glad we went with Diamond Air for our new AC and Heating system. The owner Anthony was very detail oriented when he came out to give an estimate. He's a man of his word throughout the whole process. His estimate came in with the best and most efficient name brand system at the lowest price compared to our other 3 estimates. His crew did an amazing quality installation backed by a 5 yr labor warranty. Everyone on his crew was so nice and pleasant to work with, very knowledgeable and skilled, did a excellent job, cleaned up after themselves. Everything went smooth and great! Didn't get a photo of the Furnace because it's in our attic, but here's our fabulous AC unit! It's so quiet and lots of cold air! read more

Diamond Air Services - Carrier 18 seer AC unit - Air Duct Cleaning Near Me - Ontario, California

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My air stopped working and even with changing the fuse, capacitor and filters, I still couldn't get it working. I contacted Diamond Air Services through yelp and they responded immediately. I was able to schedule an appointment for their next available slot, but they were able to come a day earlier. Their technician Howie was amazing! He was able to run his diagnostics and pinpoint the problem quickly and get my air working again. I definitely recommend this company for any AC service needed. read more

Got them through Yelp and they responded within a 10 minutes and setup an early appointment. Oscar and Baran were on time and did an amazing job. Explain me the whole thing and provided me the discounted price. I am happy with their service and adding them for annual service. Thanks Oscar and Baran. read more

These guys were lifesavers! My elderly mom's HVAC system went kaput and I had to oversee the overhaul from across the country. I was anxious about it obviously, and Anthony went the extra mile to set me at ease. The entire team was so considerate and kind, while remaining professional. I also appreciated how respectful they were e.g., when I asked questions. No one was patronizing or impatient. Manners aside, I vetted 3 companies; Diamond Air was a good mix of the benefits that come with larger corporations (licensed, detailed paperwork, dialed-down process) but with the feel of of a small, family-owned business. Price was extremely competitive, with extras in the contract that weren't offered by the other folks. I wanted Carrier (v. Lennox) which I think requires a quota to be filled in CA so some businesses don't offer them. There were no problems w/ Diamond Air b/c I guess they're a factory-authorized dealer. There were no surprises in the end, price was all-in once I signed. They were also: responsive/clear in communication, quote/contract was easy to understand, they sent photos for everything. I'm a little OCD so I loved that. Anthony runs a tight ship! Even the receptionist, Tiffany, was well-informed and able to answer initial questions about process. OK, what else...they just did a great job, cleaned up after they wrapped, paid attention to details...honest, nice folks who know what they're doing. They really took good care of us. Thank you team!! read more

Howie and his team did an excellent job installing our new heater and removing the old one. From consultation to installation to city inspection, everything was completed so quickly and efficiently. The entire process was smooth from start to finish. The price was very reasonable, and the service and communication were clear and easy throughout. They were professional, clean, and respectful of our home, making sure everything was tidy when the job was done. We also appreciated the helpful recommendations they provided. Highly recommend Howie and his team! read more

Amazing. Prompt. Efficient. Customer centered. We worked together to find the right fit for us based off of the size of unit we wanted and efficiency. They told us of discounts they have for healthcare workers (yay). But most importantly, they were highly responsive and called, even after the installation to make sure everything was OK. We ran into a little hiccup, where one of the wires was placed on a different spot (stuff happens), so the house was not cooling as it should. A technician showed up within a couple of hours of our call and fixed it right away. They said it was important that they make it right. We highly recommend! read more

We hired Diamond Air to install a whole house fan. Anthony provided our estimate at a good price and was very good with communicating with us about getting the equipment so we could schedule installation. When the team did the install they were thorough and efficient. The whole house fan is working great! read more

Our facility has utilized Diamond AC to service multiple HVAC units for several years. Every technician assigned to our site has consistently demonstrated promptness, thoroughness, and exceptional technical expertise. Their upfront communication and absolute integrity make them a highly reliable partner for our operations. I highly recommend Diamond AC for any commercial or residential HVAC needs. read more

I left two voice messages asking for a call back about an AC repair. They didn't respond.

I had a problem with my AC. It wasn't working so we called diamond air. Very fast service. They arrived the same day. Very organized. They came when they said they would. Communication was great -took pictures and explained problems. No upsell. Great price. Technicians were nice and professional. Tested my ac to make sure it worked. Definitely will use them again! read more

Absolutely phenomenal customer service, top notch quality, and very reasonable pricing! I got estimates from 4 reputable companies and Diamond Air's price was among the lowest quotes I received. More importantly, they totally surpassed my expectations in every way from the very beginning to the very end! I hired Diamond Air to install two new HVAC systems (one for my home's upstairs and one for my downstairs). The owner (Anthony) came out right away (and on time) to assess my needs and provide an estimate. He was very knowledgeable, professional, and extremely personable. He personally took care of every single detail, including managing his 4-person installation crew, stopping by my house every day on all 3 days of the installation to ensure every detail was perfect, going to the store to buy brand new air filters for me (and even gave me some extras), doing a final walk-through with me to ensure I was COMPLETELY satisfied, arranging for the testing and inspection, etc. He provided sound, experienced advice throughout the process. He noticed that there was some minor damage to the drywall along the rim of the attic opening, which was unavoidable bc they had to remove the trim around the opening to be able to fit the new equipment through the hole up into the attic. So, he promptly brought this to my attention and hired (at his own expense) a great drywall repair guy who came right away to fix everything perfectly (textured and painted to match existing ceiling). It looks better than before! Anthony checked in with me frequently throughout the installation to make sure I was satisfied in every way. And I am!!!! read more

My HVAC wasn't turning on. I called Diamond Air. I was able to have them come out next day. Sal was on time. He was able to find the problem and repair it. I was very happy with the price. I will definitely call them again. read more

Anthony came out to help us with our air conditioning, and was absolutely amazing! He solved the issue very fast, and was so friendly. We had even asked if it's possible for him to come out a little bit earlier than our scheduled appointment the day of, and he was so accommodating. We will definitely be going with Diamond Air again next time if we have any heating or aircon issues. read more

Bringing the saying, "I know a guy" to a whole new level! I have used Diamond Air on 3 separate homes, and I am always extremely happy with the service, final product, and last, but not least PRICING. I have recommended this company to many friends, and everyone has also been very satisfied. Service (10/10) I would rate higher if I could! I have been working with Anthony for a decade, and the level of customer service has always been excellent on each and every experience. He has been very professional, responsive, friendly, down to Earth, and great at explaining the process. The team that came out to install our AC unit were all very polite, put shoe covers on without even being asked, and were very friendly. Product (10/10) Diamond Air uses high quality products, does great work, and goes above and beyond with even the small details. The first AC unit they installed for me in 2014 is still going strong with no issues at all over the years. This was a complicated job; no one in my condo complex had central AC because of the difficulty of the project with no attic. They problem solved and everything went great. The mini split AC unit they recently installed has been great as well. The project was a little complicated because it was installed on the second floor, but they did great work. Wires were hidden, and the finished product was super clean. They even added a little sticker that I loved (my nickname), such a nice touch. Very happy with all of the work they have done. Cost/Value (10/10) Value for service and product is great! Anthony actually recommended that I get other quotes, and it made me appreciate Diamond Air that much more. I've had quotes from other companies come at thousands higher, and they were not even offering to do the same work or same brand level of product. I have always been extremely happy with their price point. Definitely recommend Diamond Air Services. Once you use them, you'll tell any of your friends with AC needs that, "I know a guy." ;-) Tip: They do not jack up their prices in the summer like most companies do, but they do get crazy busy during that time, so I highly recommend getting the work done in the off season like fall or winter. read more

This is my third 5-star review for Diamond Air -- and for good reason! Bobby came through again today. None of us ever want HVAC issues, but when they happen, you hope you have someone reliable to call. Bobby is that guy. He arrived right on schedule, quickly diagnosed the problem, fixed it efficiently, cleaned the unit, and even took the time to explain how the AC system works. That kind of professionalism and care is rare. Trust me -- Bobby is the person you want to save in your contacts for any HVAC needs. Thank you, Diamond Air, and a big thanks to Bobby! read more

Today I had the pleasure of meeting Salvador from Diamond Air he was very professional and he checked everything on my ac and furnace he checks everything from top to bottom great service read more

Wow! Salvador found that my Air Cond blower had died and needed to be replaced. Jose came with the new blower and installed it perfectly in 40 minutes. That has got to be a record. Both men are very good technicians; they thoroughly checked everything before leaving. Thank you Diamond Air, you are very impressive. read more

Another 5 Star review for Diamond Air from us! We had them install our AC/ heating and they did an excellent job. We recently had an issue with our AC and they were fantastic. Howie assisted us and he was absolutely wonderful - quick to respond, communicated well and addressed the issue immediately. We couldn't have asked for a better experience. Their work was excellent and done in a timely and efficient manner. We would recommend them for a new install or repairs. This is one of the best companies we've done business with. Honest, reliable and fair prices with a great group of employees. Thank you! read more

"Pretty good overall experience. The quality is solid, the service is great, and the pricing is even better. I did my research and compared at least three different companies. Some of them felt very sales-driven, but Diamond Air stood out as more professional. Whenever I asked about things like air scrubbers or humidifiers for the HVAC system, they were always able to give clear and knowledgeable advice. Unlike some companies that don't even understand what you're asking and just try to push a sale. read more