After 25 years, my Concord home needed a full HVAC replacement. I did my homework -- four quotes, verified equipment certifications, asked hard questions about duct sealing, zoning, and equipment sizing before deciding. A-1 answered every question confidently, corrected a spec error in their own quote when I caught it, and put everything in writing before I signed. Install day: Austin, Joey, and Edgar showed up on time. Floors covered, shoes covered, house treated well. Two days -- day one removal and new equipment, day two ductwork and zoning. Heating and cooling tested before they left. Full documentation handed over on the spot. No hidden charges, no surprises, no change orders. Price was mid-range among four quotes, but the warranty structure -- lifetime workmanship, no-lemon guarantee, payment at completion -- made it the best overall package. Still have HERS test-out and city inspection scheduled, but based on every step of this process I'd recommend A-1 without hesitation. Austin, Joey, and Edgar did a great job. read more

Kudos to Jonathan Meza, Maintenance/Service Tech, for the excellent customer service during my visit. I reached out to A1 because I am a repeat client who previously arranged installation of a heat pump water heater and a heat pump HVAC system in my home. This visit involved checking a UV lamp that my Ecobee app indicated was overdue for replacement. I discovered, however, that my system lacked a UV lamp. Even so, Jonathan shared more details about my setup and showed no annoyance over a call that differed from the initial report. He described the UV lamp options available for my unit and noted that he would gladly return to install one if I chose to add it to my heat pump system. For all your heat pump system needs, I strongly recommend the team at A1 Guaranteed Heating & Air. read more

Excellent service. Jonathan Meza was very nice and did a great job explaining everything. Another great experience with A-1 Guarantee!

While I was deciding to add a mini split to my 1938 home, their estimators were careful, listened to my desire to maintain as much aesthetic of the coved ceilings as possible, and were the only company who came up with creative and solid options to do so. They removed the old heat "oozer" in the living room, used the existing flue and mounted a lower unit as I was hoping. Three years later, they've been out twice for what they consider warranty work (a small pump failed) and charged me zero for the house call or the parts. They also helped me find a loan and proceeded the PGE rebates for me. read more

A 1 Guaranteed Heating & Air - I appreciate that this room unit doesn't interfere with the coved ceilings. Both bedrooms have the more standard ceiling mounted units. - Heating & Air Conditioning/HVAC Near Me - Vallejo, California

So it's that time of year again. Inspection and tune up on the furnace Jake my technician was on time spent an hour on the unit and then took the time to explain all he did. Written report was also supplied Can't say enough good things about this company. Everyone there is so professional and helpful! Definite recommend to my family and friends read more

Since A1 upgraded my insulation, converted me to a heat pump and now manages my maintenance plan, all of their services have been wonderful. They've proactively let me know if parts needed to be replaced. All the technicians, like Roy who was here yesterday for my regular maintenance visit, are incredibly competent, efficient and gracious. Thanks also to Jessica who helped me with scheduling. I feel very well taken care of. Unreserved recommendation. read more

One of my tenants was sure her thermostat was beeping. My regular guy was unavailable so I called A 1. They were professional and low key. We set up an appointment for a tech to visit and the woman who helped then explained the pricing very clearly and simply. No surprises. Today the tech, Eric, came out to take a look. He went into the apartment and immediately found the beep. It was actually coming from an old CO2 monitor that the tenant had put under some clothing! He was very kind about it and reassured her that it happens all the time since she felt rather foolish. He then just said "No charge." And he left. What a great person, Eric, not only to figure it out so fast but also to be so kind. Thank you Eric and thank you A1! I will certainly use you folks in future. read more

Could not be more pleased. Needing to replace our 40 yo gas furnace we decided to get an HVAC system. Got three bids. A-1 submitted the lowest bid and it was easy to choose them because they had already installed two systems on our block and our neighbors were very pleased. Sales Manager Kirk communicated really well, providing clear answers to our questions and making no change to the bid when we decided to change the location of the outside unit. Perhaps lucky for us, they were able to install in less than a week. Carrier brand equipment, which uses variable speed technology from Toshiba. A crew of four completed almost all the work in one day. Our existing ducts were not being replaced (both A-1 and another bidder saw no reason to replace them whereas the third bidder wanted to replace them at great cost). Nevertheless, fairly substantial sections of the ducts were indeed replaced in connecting to the new system. All the work was really well done, neatly and with complete clean-up and disposal of the old materials. Ducts were completely insulated, including new insulation on old sections. A-1 also pulled the permit, arranged the needed post-installation duct test and the final City inspection. read more

We are pleased with A-1 Heating & Air Company with its excellent service in replacing our old leaking water heater. Office staff was friendly, professional and courteous. Nick even came to our home and helped us empty the water from the leaking heater on the same day. Matt H. answered all of our questions and gave us a reasonable and competitive quote that includes their standard one year warranty for labor and materials. Mason did a great job installing the water heater the next day and made sure that the water heater is working properly. We highly recommend A-1 Heating & Air for HVAC, Water Heater and many other services. read more

Leaving another 5 star review for A-1 Guaranteed. A-1 sold and installed new HVAC and PV Solar systems for us in 2017. The sales and installation experience were both excellent. Every detail was handle with care. Top quality! Now, 8 years later I am so happy to share that the servicing experience with A-1 has also been the best. They go the extra mile every time to provide the best service. You know that good feeling when you have found a top notch contractor - that's been my experience with A-1 - everyone from the office, scheduling, and billing folks, to the techs, to the owners (and family). So glad I went with A-1. Special thanks to Nick (solar) and Jake (HVAC) for your great work today. Decided to head right for the computer and leave this follow-up review following your excellent work today. read more

Great company, great people. I have A-1 Guarantee installed new Heat Pump, AC and Heating unit few years ago. This company also have maintenance services at low price which I am signed maintenance contract. It is easy to make appointments with them. I don't have any problem with this company. read more

Believe the hype, these guys are amazing! Erik was professional and quick, but thorough. As a first time homeowner, I greatly appreciated how informative he was about everything and laying out all my options. No pressure to do anything that was not needed right away and made the whole process so easy. I tried to hire them last year for an AC repair during a heat wave, but they were booked solid and gave me a referral for another company and let me just say, the service is night and day. I can't recommend them enough! read more

I have been a completely satisfied customer of A-1 for many years. I wisely signed up for the Kelsey Club maintenance plan which has insured the flawless operation of my heat pump heating and air conditioning unit. On my January maintenance I was really impressed with Jake's meticulous inspection and report. Which has mirrored my previous interactions with A-1. read more

Great job A-1 Guaranteed Heating & Cooling! Kudos to project lead Matt H, and installers Jose and Edgar for quality and excellent work on my new Bryant replacement air-conditioning unit. I will definitely recommend A-1 Guaranteed to anyone needing an air-conditioning project. read more

A 1 Guaranteed Heating & Air - My new 3-ton Bryant outdoor condensing unit. Perfect fit and quality work from A-1 Guaranteed H & C. - Heating & Air Conditioning/HVAC Near Me - Vallejo, California

Didn't get to do a project with them but A1 goes above and beyond answering my questions! Genuinely honest and exceptional communication.

From beginning to completion, we have been immensely satisfied with A-1. Kirk visited our home a couple of times, spending the considerable time needed to do a close examination of our house and answer a long list of questions. He knew his stuff and provided information we hadn't even thought to ask. The foreman who followed up with a pre-install visit and the crew who spent a few days on-site doing the work itself were respectful, efficient, skillful, and even joyful in their work together. We are incredibly glad we finally had this long-anticipated project completed and couldn't be happier with the results and the service A-1 provided. read more

A-1 Guaranteed Heating & Air, Inc., a family owned and operated business, were absolutely awesome! Matt Hiteshew, Comfort Advisor, came out and provided me with a quote on a new Bryant Air Conditioner to replace my old Carrier. Matt was professional, extremely knowledgeable, very honest and provided me with an excellent price on a new Bryant Air Conditioner. Matt provided excellent customer service, was very pleasant and knew exactly what I needed and did not try to sell me something I did not need. The installers, Larry and Edgar did a superb job with the installation. They were respectful, knowledgeable, answered all my questions and did a wonderful job cleaning up after the installation. The office staff, Courtney, Jessica and Kenya were great! They were all very friendly, helpful and responsive to my questions and needs. I will use A-1 Guaranteed Heating & Air, Inc., for all my future heating and air conditioning needs. A-1 Guaranteed Heating & Air Inc., is simply the BEST! read more

I decided to get AC in my Vallejo home and went thru multiple quotes. Matt came out and explained everything to me and went over all of my options. He was so professional and thorough I felt really informed after the initial meeting. It never felt like he was trying to oversell it just seemed honest and informative. That was my first quote and I liked the company so much I was worried my other quotes would be less causing a difficult decision. Well... nope my A-1 quote was THOUSANDS less than the competing bids. Also in other bids I was told It would take anywhere from 2 to 4 days to install while A-1 offered installation in one day. I ended up getting AC and replacing my old furnace. The installation went so smoothly. The team were so great and left my home cleaner than it was when they came. Every interaction I have had with them whether in person or over the phone with scheduling has been fantastic. They are wonderful to work with!!! Also my air conditioner is amazing and I'm so happy with my choice to use this company. read more

Great team and excellent service! When other companies came in and said "you need a brand new system!" And "aren't you worried about safety?" A-1 techs just come in with experience and credibility to diagnose and fix whatever is wrong. They have serviced my A/C as well as the furnace. From a new gas valve to a new relay, capacitor, and motherboard over the years. They have kept my 30 yr old system running perfectly. Most of my neighbors now use them too! Great value for $$$! read more

Jorge was punctual, friendly, and professional. He performed scheduled maintenance on my system in a timely manner. He is an excellent representative of A-1. read more

Another amazing visit today by Tyler and A-1 Guaranteed! A-1 Guaranteed fixed our air conditioning unit at our old house about 18 years ago, when no one else could. Since then I have had a service contract and they visit twice a year. I moved my service to our new home in 2017 which has dual air conditioner and heating units. Tyler visits twice a year and services the equipment. Several years ago a module went out in the middle of summer. Tyler came right out and got the system repaired. I can't praise A-1 Guaranteed enough and everyone should use them! The best testimony is an 18-year customer that has regular visits! Best to have a service contract and maintain your units as those systems are the most expense in your house! I completely trust A-1 Guaranteed. Thank you to Tyler for always being the star tech! He knows our house and always reviews the work he performs! Simply the best! read more

I switched to using A-1 (and their Kasey's Klub membership) about 6 months ago and have had them come out a couple times. They are professional, knowledgeable, respectful, prompt, and very informative. In short: they're everything you would want in this kind of service. They're solid and I am happy to continue using them. We use them for regularly servicing our HVAC and A/C unit. P.s. specifically, Jorge came out today and was fantastic! read more

We had Joe B. from A-1 Guaranteed Heating & AIr out yesterday to repair our heater. We had been without heat for the past 15 days. Joe came out last week & found the problem & had to order the parts. He had the day off yesterday but came into work to help 2 custometers out, one being my Mom & I. He was here from 1pm until 5:30pm. One of the parts ordered ended up being the wrong one but he was able to leave for a "minute" to get the right one and come right back here. Talk about Teamwork ~ he worked with tech support and another tech came out after the sun had set. And it was raining (our unit is out back). Joe simply would not leave until Mom & I had HEAT!!!!!!! He is THE BEST! To say we are impressed by this company and their amazing employees is an understatement. I would and will recommend them to any & everyone! From the office staff to the techs in the field ~ THANK YOU FOR BEING SO AMAZING!!!!!!!!!!!!!! Thank you, thank you, THANK YOU!!!!!!!! read more

We contacted A-1 Guaranteed 2 months back when we decided to switch out the 25 plus year old gas furnace from the home we purchased in Berkeley in 2020. the previous winter the gas furnace stopped working after a part went bad and had to replaced (luckily covered under the home appliance warranty. After researching about different Heat pump HVAC systems along with potentially replacing our central air ducts we found many incentives through East Bay Community Energy to switch to electric. Some of the resources can be found through the switchison.org, Tech Clean California and BayRen. A-1 guaranteed Heating and AC is listed among the certified contractors which is required to qualify for the incentives. I was very impressed from the get go with how thorough and professional the team were. Kirk, who is one of the senior sales representatives from A-1 Guaranteed Heating in Vallejo came out 2-3 days after we requested an appointment and went over the process of replacing the gas furnace and installing a new heat pump HVAC including the technical details between the 2 systems. He also provided us education on how they evaluate the home's attic and wall insulation as well as the condition of the ducts. Kirk explained that the condition of the ducts and insulation were equally important to installing a new heating system to make sure that any newly installed system would be designed to run at the highest level of efficiency and comfort. After reviewing all the incentives for our zip code we decided to replace the air ducts and switch to the HVAC heat pump. A-1 Guaranteed heating did a thorough evaluation of our level of insulation to make sure that the system would be sized appropriately. Fortunately our home only required a 2 ton heat pump and they had a fujitsu model in stock. (considered one of the better heat pumps) Kirk also explained that the bid included all the costs including material, labor and permits from the city of Berkeley which requires an city inspection. We did seek out some other bids from other local Heating HVAC installers in the east bay but most were saying it would be 1-2 months before they could even come out to do an evaluation or the other companies' bids were much much higher for the same service and products. Even after accepting their bid if we had any questions or clarifications no matter how small the issue was Kirk would reply promptly answering all our queries. Also the scheduling staff always communicated with us well in advance about potential dates and times for the installations and to confirm that that these times would work for our schedule. Even reminding us of the scheduled dates when BayRen or the city inspectors would coming out to complete their inspections. When the HVAC installers came to our home they all seemed very skilled. Also they were very clean, followed recommended covid protocols and were considerate about keeping us apprised of any items where they or we needed clarification. All the work was completed including the city inspections with 6 weeks which given all the supply chain issues is in record time from what I can tell. After they completed the installation the technicians also let us know that we should monitor how the air flow was in each of the rooms for sometime and if any adjustments that we felt were needed, they would come back and make the adjustments. In our case about 1 week later we decided that one of the ducts did need to be adjusted. After reaching out to Kirk within 1-2 day the technicians came out and rectified the situation. Overall the A-1 Guaranteed Heating and AC team has been a model experience and we felt the team not only placed a value on providing excellent qualified technical installation services but also on providing a great customer experience as well and we highly recommend them. read more

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We've been using A-1 for our service needs for years. It was finally time to replace our 24 year old HVAC system, so of course we got estimates from as many different providers as possible. The proposal from A-1 was competitive and professional and comprehensive. They replaced all the parts of our HVAC system, including the duct work in the attic. The installation was smooth and they did a great job - especially making sure everything was working properly and everything was cleaned up afterwards. We've had the system for 6 months now, and not a single problem - even more important, our house has never been more comfortable - even the hot summer was more comfortable than it's ever been since we moved to Dixon. Thank you, A-1! read more

Excellent service twice a year. Very pleased with service. Does a thorough job on both heater and Air Conditioner.

Very pleased with the excellent service provided by Tyler. He did a thorough review and addressed all of our questions. Very friendly and respectful of our property. read more

Krissy Hiteshaw, owner of A-1 Guaranteed Heating and Air just sent an email to be very sure everything is working well on our new system. How nice to have this kind of follow up! Please consider using this great company. read more

Very pleased didn't try and sell you something you didn't need will definitely call on them again

A-1 recently installed a new heat pump for us. They were professional, on-time, helpful and cleaned up after the installation. This is the second job they've done for us. The first was a replacement of the old heating system at our daughters house with a new HVAC system. There they also did a great job. I would highly recommend them for any heating or cooling job. They are great! read more

Excellent customer service and great work! No complaints on my experience with a water heater and furnace installation.

Amazing family owned business very honest efficient business. They won't tell you you need things that you don't need. They're on time and reliable service is excellent. read more

We had duct work and our furnace relocated to our attic. The work was completed 1 year ago, so I thought I would let you know how everything has been going... FANTASTIC!!! As first time home buyers, we had NO clue what do about our lack of heating/air. All we knew was that our house would not cool down. We called around to numerous companies until we found A-1. Their price was very competitive, and their service is top tier! After getting the run around and crazy expensive quotes we went with A-1 and they have exceeded our expectations. I feel it's important for potential customers to know that my workmanship is holding up wonderfully. It felt so good going through the heatwaves with a cool home!! THANK YOU read more

My husband and I were thinking of installing central heat and air in our home and a friend of mine suggested I call A-1Guaranteed, she had heard good things about them and were highly rated. I contacted A-1Guaranteed Matt came to our home to give us an estimate, he was very professional, friendly and answered all our questions. We had two other companies come out and I can definitely say, we felt most confortable with A-1 Guarantee doing the job. The job was completed within the time frame Matt said, two days. The team was on time every day, they were very friendly and cleaned after themselves at the end of the day. The work went smoothly and we are so happy with the results! I would highly recommend them. I would also like to mention that the office staff, Kenya, was very patient and helpful with with all the questions I had. Thank You A-1 ! read more

A-1 Guaranteed Heating & Air recently installed a ducted mini-split heat pump system in my 80 year old house. The project initially seemed daunting to me, but it went smoothly, as the team was courteous, prompt and professional from the first phone call to the final follow-up appointment. They responded kindly and thoroughly to my questions and concerns and resolved any issues that were unique to my house. I highly recommend them. Outstanding customer service and top quality work! read more

We have been customers with A1 for over 35 years. Each job and upgrade they have completed for is is handled perfectly. One furnace had an odd vibration that just could not be locate. One day the installer shows up and says he has an idea what was causing vibration. He did his magic and found the problem, a simple fix was the answer. Today Brian came by for the semi-annual checkup. He knows where everything is. No issues. Will see him in December. A-1 is the best there is and they are a longtime local business that does a lot in the community. read more

I recently called this company to have a look at my furnace and to do a complete service, years ago I had used them on several occasions, (approximately 20) on all my Real Estate listings. They now refuse to come out unless you belong to their maintenance program. I now use another local company for all my needs. It's a shame they just lost another customer to their stupid business decisions. read more

They visited our home and provided a written quote, including all the major components and a fixed price. They arrived at the appointed time, did all the work in one day, and left the job site clean and neat. Also, they quickly answered all our questions. We would recommend them to our friends and neighbors, and would consider using the company for other work such as water heater installation. read more

For an outfit that charges a high"maintenance", I found them unresponsive to a situation that should have had quick attention. It took more than 24 hours for a return phone call. We have found another service. read more

We have been using A-1 for over 20 years and have never been disappointed. Jorge came out today to service our heat pump system. He texted me when he was on the way and arrived on time. He was very personable, knowledgeable, and was able to answer my questions. Overall, the service was perfect. read more