HVAC reviews in Hacienda Heights, California

Lexus has fix multiple of my friends and family air conditioning problems. He is very honest and friendly. If it's a small problem he will only charge small problem price. He never try to upsale you for more parts or over charge for small problems or easy fix. Great pricing and friendly 👍

A professional HVAC company IN SOUTH CALIFORNIA . Applied permit, finished installation and one time passed city inspection! Very reliable!

We hired Dr. Dio in 2024 right before one of the hottest summers, just as we were about to welcome our first child. During that time, we discovered asbestos and severely damaged AC ducts in our attic, so it was a stressful situation to say the least.
After getting multiple quotes, Dr. Dio offered the best price by far. The timing couldn’t have been more intense — the day before the scheduled asbestos removal and AC installation, our baby was born. Thankfully, my mom was able to be there while the work was being done.
Dr. Dio and his team exceeded expectations. They completed everything faster than promised, and by the time we came home from the hospital with our newborn, the entire system was up and running perfectly. It was over 106 degrees outside, and our home was cool and comfortable.
It’s now March 2026, and the AC system is still working great. I’m genuinely grateful for the quality of work and professionalism. I continue to recommend Dr. Dio to friends whenever they need services.

I had an amazing experience with Dr. Dio Heating & Air Conditioning! Dio is incredibly experienced, fast, efficient, and knowledgeable, with reasonable prices. On top of that, he keeps everything clean and professional from start to finish.

Even though he primarily services the L.A. County area, he went out of his way to come out to San Bernardino County for me, which I truly appreciate. Thanks to his excellent work, I'm now enjoying a perfectly cool and comfortable home.

I'm beyond satisfied with the service and highly recommend Dr. Dio Heating & Air Conditioning to anyone in need of reliable HVAC work.
You won't be disappointed!

I recently had all of my air ducts replaced by Dr. Dio and his crew, and I couldn’t be more impressed with the entire experience. From start to finish, they were punctual, professional, and incredibly respectful of my home. They took great care to cover all work areas and left everything spotless once the job was complete.

What really sets Dr. Dio apart is his honesty and expertise. It’s clear he has many years of experience—he takes the time to thoroughly explain everything and never pressures you into unnecessary work. In fact, he’ll let you know if something can wait or doesn’t need to be fixed at all, which is refreshing compared to some larger companies that tend to upsell.

Dr. Dio is not only highly skilled but also genuinely friendly and easy to work with. You can tell he has built his family-owned business on integrity, quality workmanship, and a true commitment to his customers. His pricing is very competitive, and he stands behind the work he does.

I would absolutely recommend Dr. Dio to family, friends, neighbors—anyone in need of heating and air conditioning services. Thank you, Dr. Dio, and your entire crew for an outstanding job!

Professional 5 star service thank you God bless

If you’re looking for an AC guy, give Dio a call. He will do what is in your best interests rather than doing what makes him the most money. Trustworthy and does fantastic work. He even left my place cleaner than he found it.

Dr. Dio came to my house before his first appointment and fix the problem. He lent me a capacitor in the meantime. He came back the same day and replaced it with a new one. He saved me a few hundred dollars. I highly recommend him. Lisa C 👍😊

First time home owner and wasn't sure what to do about our HVAC issues. Dr. Dio was an absolute delight to have over and helped us diagnose and fix the issue at hand and even described potential future issues to look out for. 100% will be my go to technician for any HVAC problems! Thanks alot!

Update on 09/17/25: Dr. Dio comes through yet again! Our capacitor crapped out on us last night and Dr. Dio came through for us. We called him and he walked us through it because he could not make it out today due to a large HVAC job he's got going right now. We are always grateful that he attempts to diagnose the issue and save the customer money so he doesn't have to come out. That's how I found him in the first place. Our AC had gone out a few years ago and he figured out what the issue was by walking us through some steps thereby saving us money since you can fix it yourself. Who does that nowadays? Dr. Dio does. He always comes through for us.

Original post: I don't know why I had never reviewed this business before. Dr. Dio had previously done an installation of a new HVAC unit at my mother's house in early Dec. of 2017. That job entailed new duct work since her house had been built in 1971 with only central heating. Dr. Dio had done an awesome job with that so we call him for regular maintenance on that unit (annual check-ups). Last year, our regular HVAC guy at our house retired so now Dr. Dio is our HVAC guy at our house, too. (My husband had used his own guy for something like 20 yrs. so he didn't want to try my guy out of loyalty to his, you know?) Fast forward to present: our A/C died suddenly this weekend so Dr. Dio came out today and saved the day. He came out, diagnosed the issue, had the part available thankfully, and took care of our A/C problem. Didn't charge us an outrageous price, either. He's honest and upfront about everything he finds when he comes out to diagnose your issue and gives you good advice to keep your unit running at its optimum and I truly appreciate that. I had originally found Dr. Dio on Yelp when our A/C broke down in the middle of a hot summer about 6 years ago on the weekend and no one could come out right away due to the heat wave. I had called a few people and Dr. Dio had actually told me over the phone how to fix the issue if we were handy. We're not handy, though. :) I made a note to use Dr. Dio when I needed an HVAC guy in the future and that's how we ended up using him for my mother's installation of a new HVAC unit after comparing him to other quotes. He was honest and gave us good vibes and his quote came out on top. I have no reservations about recommending Dr. Dio to anyone.

Dr Dio came out and fixed our ac.
Not only did he fix it but he also provided excellent customer service! Very honest man. I didn’t feel cheated or scammed with my money! I will definitely be referring Dr. Dio to my family and friends.

We had a great experience with Dr.Dio. My air conditioning unit was having issues, and he was quick to respond, professional, and honest about the work that needed to be done. He explained why the unit wasn’t working and didn't try to upsell unnecessary services like other companies. The job was done efficiently, and my AC is now working perfectly.

My AC decided to break down during a heatwave and I was desperate to have someone come out right away. I immediately reached out to my dad because I wanted to use his guy (Dio). Despite being super busy, Dio was quick to respond to me and even offered to come out himself the next day even though I'm *WAY* out of his service area! Talk about service!

Dio diagnosed the problem when I first texted him and his in-person visit confirmed his suspicions. I was extra confident with his assessment because I reached out to my friend's husband who also owns his own AC company and he suspected the same problem.

Dio also made a great recommendation for a safety valve so the AC would automatically shut off if leaking were to occur in the future. He always looks out for his customers!

If you're looking for an AC guy, don't hesitate to contact Dio. I could have easily called any random person to service my AC but why would I want to risk going with a stranger? It's hard to find reliable and trustworthy vendors these days so take it from me and call Dio!

I can’t say enough good things about Dr Dio. This man is a true professional. His team and he are hardworking and knowledgeable. I needed to replace my Dad’s heating/air system after he passed away and Dr Dio was compassionate, kind, honest, fair, and wise in explaining the work needed. It was a really positive experience during a difficult time. Once you meet Dr Dio, you won’t want to hire anyone else!

This is the second time I have used Dr Dio for my a/c problem. The first time, he came right away to fix the problem and his labor was inexpensive for a minor problem.
This morning, my a/c was not working again, but it was a different problem, so thru texting he walked me through to troubleshoot the problem with his diagnosis.
With his guidance, I was able to get the a/c working again. He saved me money and I didn’t pay anything.
He is an awesome and honest a/c repair person.

I had a fantastic experience with Dio when my split unit AC suddenly stopped working. He responded incredibly fast and was at my house within an hour of my call. Dio quickly diagnosed the problem (a refrigerant leak) and clearly explained everything he was doing to fix it. He kept me informed throughout the entire process, which I really appreciated. His excellent communication and professionalism put me at ease. The price for the repair was very fair, and I felt confident I was in good hands. I highly recommend Dio and for any AC issues!

Dr Dio was extremely helpful and responsive every step of the way. He was detailed on everything, showed me videos and photos of what was going on, and explained everything in an easy to understand way. My heater stopped heating and he made time to go above and beyond with his service, making time to fit me into his schedule and saving me money by figuring out a way to fix what I have and not trying to sell me a new system. I appreciated his transparency and honesty and I'll definitely be using him for future services due to his overall professionalism!

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I hired Dr. Dio to fix a leaking air vent, and he did a great job. He is honest, explains issues clearly, and offers different options without any pressure. He takes the time to answer questions, which I really appreciate. I have used him multiple times, and the work is always done quickly, professionally, and with excellent results. Highly recommend Dr. Dio for your aircon/heating needs.

"Had everything waiting at the dock for me."

"Amazing service. The team is very customer service oriented and extremely knowledgeable. "

Great distributor specifically for hydronic heated equipment, and thru the well equipment.