Recently, I needed repair services for a 1970's boiler for a baseboard heating system. The system had been randomly failing to turn on. Andy arrived, took one look at the system, and immediately identified the problem (corroded valve). He then efficiently fixed it in a reasonable amount of time, at a fair price. Than you, Andy! So grateful for the great service from Carroll Mechanical, for three different properties now over the past 2 years. When you find a knowledgeable, fair, quality contractor, you keep calling them. Carroll is my go-to for all HVAC, highly recommended! read more

CMS is now owned by Welzig. I really liked CMS for general service because they never tried to sell me anything, they just came and serviced what I have and kept it running in top shape. I hired Welzig once, and a CMS technician showed up to do the service. He did the work quickly and replaced my humidifier contactor pad for free, but then the selling started. Replace my perfectly good Honeywell thermostat with a smart controller ($500+) that uses forecasts from the internet instead of the house temperature to decide when to run. Clean the ducts for $1,000 (do they know about the ValPak $299 company?). Add a water alarm device for $500 (I already have one from a multipack I got at Costco for $20). Literally $10k in recommended "improvements", and they really really wanted me to sign up for a service membership. Sure I get my tune ups, but also a plumbing and electrical consult I don't need each year. I have no confidence whatsoever they wouldn't intentionally damage or fail to service my unit in order to get me to buy a new one. I'm a redneck engineer from the South. I'm used to chainsawing my way out of the neighborhood after hurricanes, building blast furnaces using old lawnmowers, and cobbling together whatever I'm wanting to make (chicken coops, rabbit hutches, fences, you name it) out of whatever scraps are laying around or free on Craigslist. I'm scrappier and more miserly than most, but for those like me who are inclined to open their condenser when it stops running instead of calling an HVAC company to spend $250 on diagnostics, this is not the company for you anymore. read more

They got bought out by welzig. I did not have a good experience with welzig. Technician was smelly. Did not diagnose correctly. read more

We highly recommend CMS- a family-owned business based in Longmont- for any hvac service or replacement! Brien's furnace replacement crew of Lawrence and Zach were very prompt, personable, and professional. They replaced our old 80%-efficiency furnace with a 95% Carrier model in less than 8 hours, made absolutely sure that everything was done right and to Boco code, and left no speck of debris or trash. To top it all off, Brien's bid was VERY competitive with all other bids, he helped us apply for an Xcel rebate, and he offers a 2% discount for payments by check. This is a great local business, you'll be glad you hired them! -Tim in Longmont read more

I like these people. I have a quirky issue with 2nd stage on my heater that they (Hugh) can actually explain where previous company that installed it could not. They recently did seasonal maintenance on AC and included washing off outside unit where previous company wanted me to set up a special appointment just for that outside normal AC maintenance. They listened to me regarding funny noise that was driving me so crazy I would turn my AC to a warmer setting at night just so I wouldn't have to hear it. We couldn't replicate it during the visit, but Sage tightened up top grill and I haven't heard it since! Nice people. read more

SO GRATEFUL! I have had trouble with the blower motor on my heater for two years, bouncing from company to company and even having to fix it myself at one point. I had given up on HVAC companies after having so much trouble. CMS blew my mind, so professional, so fast, so GREAT! They replaced my entire rickety old system with a new no fuss high tech system IN ONE AFTERNOON! My house, in the middle of winter mind, didn't even have enough time to cool down and the new one was blasting (quietly) warm comforting air like it never had before! You will get so much more than you expected from CMS, you will not regret making the decision to have CMS come to your home and make everything all better. read more

My husband and I used this company. We had no heat. It took them 5 days to come and do the repair. The first time they canceled I was told that they forgot about our scheduled appointment and she forgot to order the part, I was promised they would be at our house the next day to fix it. Thenext day we got another call to tell us they were not coming. We would never recommend or use this company again. If thinking of using them,I would suggest someone else. We were so disappointed. We try and use local companies to help the community. This company is a Hugh disappointment. read more

We've hired them several times to clean and repair a gas-fired hydronic system in a rental house in Longmont, and they've always done a good job. Work included cleaning and inspection, replacing a solenoid valve, and replacing a water pump. They responded quickly and arrived on time for each of these jobs and did careful work. read more

I had Carroll Mechanical Services install a A/C unit for my Condo after the original unit that was 14 years old died. Brien the owner came out and did a evaluation of my system, quoted me a price which included a $200 coupon that they were offering and gave me a Military discount of $600 as well! The crew arrived when they said they would and did a fantastic job! When the Building Inspector came to evaluate their work, he said that Carroll Mechanical Services always does a good job. I would recommend Carroll Mechanical Services to anyone that needs HVAC work done! read more

Carroll Mechanical came out to replace our furnace, A/C, and water heater. They were able to come out quickly and completed the work in a timely and professional manner. And the new furnace came with a really cool Ecobee smart thermostat that we love! read more

Stan with CMS performed the annual inspection of the HVAC system and identified the need for a new blower. Stan replaced the blower and capacitor on the HVAC system ($548.74). Upon completion, Stan was shown that water had begun to leak into the corridor below. Stan went to his next appointment without addressing the leak. Andy responded to our emergency call at 11PM and drilled holes in the drywall to vent the water (CMS did not charge for this call). Stan decided the water heater needed to be replaced (we asked for a different tech, but Diana said we had to wait 2 weeks). A written estimate for a new water heater was $1095. After the water heater was installed the owner Brien demanded immediate payment of $1221.55 plus tax (claiming his staff forgot the cost of an expansion tank). The drywall leaks continued after the water heater was installed. Brien recommended we hire a plumber. Our plumber found a disconnected pipe for the pan under the water heater (he charged $330 to repair the pipe, plus $120 for drywall repair). This pan was collecting condensation from the air conditioner. The logical explanation is that Stan broke the pipe during the blower installation. We did not need a new water heater. We now question the need for the new blower and capacitor. Notes: We are experienced property managers having owned over a dozen apartments. This is our only out of town property and we lease it to our handicapped son. We regret placing our trust in CMS. We sent this description to Brien at CMS 3 weeks ago and have received no reply. The water heater failed the building inspection and CMS did not follow-up to fix the system. We paid our plumber to install a misdirected drain pipe. read more

The team was so professional and they didn't upsell me! I really appreciated working with Carroll Mechanical to get my new AC/Furnace installed. They gave us an honest quote and even offered us a discount for my wife being an ER nurse during the COVID situation! The install was very easy and they followed all safety protocol with wearing masks and gloves... and of course, they explained everything from soup to nuts. I would recommend them for anyone looking for an honest and friendly repair or installation of AC or Heating. 5 stars all around. read more

Brien Carroll is awesome. He's very knowledgeable, professional, and an easy going guy. A few years ago, the old furnace in my rental property was starting to make a horrible noise. Instead of taking advantage of my ignorance, he told me the problem was no big deal, and that the fan happened to have been bent at some point. He took about 10 minutes to fix the problem and charged me a fair price. A couple of winters later the furnace was having problems again. This time I didn't hesitate to just replace it - even though he was confident he could fix the problem. I just didn't want to deal with any more problems. I had tenants living in the unit at the time and the winters in Boulder can be brutal. Within one week he had replaced the furnace. I was shocked with how nice the end product looked. I was so happy with it, I decided to have Brien replace the water heater. He and his crew did a great job, for a fair price. They even laid down plastic so they wouldn't bring snow and dirt into the apartment with their shoes while they worked. Two thumbs up. read more

I called Carroll Mechanical Services around 1pm on Tuesday, they said they could be here by 3pm same day. At 3pm, Andy showed up and was very personable and made me comfortable right away. He went right to work and found the problem very quickly. He repaired the problem, cleaned the unit and the filters and checked that it was working properly and only charged me for one hour of his time. He was actually here for one hour, but I think he could have taken longer and charged more and I would not have known an better. I am very happy with the entire experience and will call Carroll Mechanical again for any heating, air conditioning or water heater service issues I have. read more

We used CMS to clean, inspect and certify our furnaces as part of our home sale. They were prompt, honest and very reasonable. $85/furnace. By comparison M&M was going to charge $135/furnace for cleaning/inspection and $120/furnace for certification. read more

Dale was excellent and thorough. He fixed a problem that another company said would have to wait until spring.

We had them come out for an annual Home Boiler/heater service. I left town for several days after that-when I reeturned there was a strong smell of natural gas-I left the house and called Our gas company and Carroll Mechanical. The gas company turned off the gas and told me where the line break was and mentioned that it happened with the recent service by CMS. CMS came out and made the repair but charged me at the after hours rate and for the parts. I contacted the owner with a letter-NO RESPONSE. They offer NO WARRANTY on their services obviously!!!! read more

Had someone from CMS come over to look at ducting to see if they could determine why one half of the house was getting a lot more heat than the other side of the house. It turns out that the flow from the furnace was uneven from the get go. Technician then took measurements and suggested that placing some vanes in the ducts might improve the situation. However, after taking the measurements, I never heard from CMS again. Called several weeks later left a message asking why no one ever followed up. Never heard from them again. So it was a waste of money. read more

We choose Carroll Mechanical to install our evaporative cooler because of great reviews and after meeting him and getting a quote. This was our second summer using it. The unit is fantastic. They did a great job installing and such. I cannot believe what a big difference the cooler has made in our house. We can no longer imagine being without it. Brian has been attentive and professional. We use their service also in spring to start up and now in the fall for shut down. Great company. read more

We have lived in Longmont for three years now, I have used Brothers and Twin Peaks to service our house furnace prior to discovering CMS through the positive reviews here on Yelp. We wanted to install a "mini split" AC system in our ductless home. Brien Carroll was one of three estimates that we received and beat both the Lennox (Costco) team and Sears by more than $3500. Not only was the estimate fair and reasonable, but the work was done on time and as planned. Very happy does not cover it. I would highly recommend CMS for any HVAC work you need. Brien cares about his business and it shows in how he treats his clients. read more

Fair prices. Very honest and straightforward to deal with Brien. Considerate and tidy install crew. One of my best experiences with a service company. read more

I can't say enough about how great Brien and his crew are. His pricing is very competitive. And his responses to my questions prior to the service were very quick. We needed a new furnace install. When they did the install, they were very clean and professional. Brien followed up a few days later, and we settled the bill. He is a great guy to work with, very honest, and values you as a customer. read more

Everything about working with CMS was easy and pleasurable. From the reservation process and pricing. To timely technician, who used the who hour I was paying for to make sure everything else was working properly too. I will definitely be using CMS for any other A.C. or heating needs! read more

We had the good fortune of finding Brien Carroll when we our hot water heater was having issues at our rental property. Brien came out and fixed the problem and also thoroughly cleaned out all of the burner parts on what is a somewhat complicated assembly due to the forced venting requirements of the unit. He brought the old water heater back to life! I was so happy with his work that I brought him back the next week to do regular maintenance/cleaning on the furnace at our rental property and our actual house. His work on both furnaces was top notch and both were thoroughly taken apart, cleaned, oiled, etc. at an extremely reasonable rate. When our old hot water heater finally gave out I called Brien who was able to complete the job with no advance notice on a Saturday morning (ruining his weekend plans) for our renters because they were having guests over the weekend and would have otherwise been stuck with cold water (and again he did all of this work efficiently and at a fair fixed rate). After these events Brien is the first and only call I make for any plumbing and heating or cooling problems I have at our house or rental property. He is a stand up guy who I completely trust to do superior work at a fair price and it's taken some of the stress out of having a rental property knowing exactly who to call when something goes wrong. read more

I own a commercial space in Boulder and our heat suddenly stopped working this morning. I found Carroll Mechanical Services here on Yelp and called them to see if they could send someone out for an emergency service visit. The lady that answered the phone (Janet) was super nice and let me know their schedule was pretty booked today. She said she would see if they could fit me in and would call me back within 10 minutes. She actually called me back within 10 minutes! And confirmed an appointment for within the hour! They sent Joe out to my place. Not only was he early, but I found him to be extremely knowledgeable and personable. He was able to quickly diagnose what was wrong and fix it. I appreciate that they were able to fit me in on such short notice - as well as the friendliness and integrity of everyone I came in contact with on their team. I will definitely be contacting Carroll Mechanical Services again if the need arises and highly recommend them. read more

We've had 3 companies come and replace our zone valves. The first one charged $450 to replace one, the second charged $150 and CMS charged $85 to replace TWO. I love CMS and will always use them going fwd. read more

Fair, honest, and no BS contract terms and conditions that add backdoor costs to my furnace install. They assessed my old furnace, provided me with a fair quote, not the cheapest or the most expensive- but when you take into account the warranty and business reputation, I made the right pick. The furnace has been in for a few days and its working great and I'm happy that CMS will be the ones servicing my furnace (and HVAC when I upgrade one day). Shop around, but remember a warranty is as only good as the company and people backing it. read more

CMS did a great job. Needed a part that required a great deal of time for CMS to obtain. CMS cheerfully put in the time and got the part into our furnace promptly with little down time. read more

I have seen CMS van in our area so I gave them a cal l about our water leak in our furnace. They sent Andy to our house in about 3 hours after the call. Andy was great, he spent more than a hour to isolate and fix the leak. When he noticed my humidifier not working due to a clot in the water line, he fixed it without additional charge. We are very happy with the whole experience and definitely would use them again. read more

Horrible company. They have no idea about HVAC. They cannot even fill up freon for AC. They don't believe in customer service either. I won't bother calling him for HVAC or anything else. If there is less than one star, I would give them. read more

I have been using Carroll Mechanical Services for several years now to perform routine maintenance on my heating and air conditioning system. They have always been professional, prompt, friendly, and I've been able to schedule the service call quickly. Very good prices. Highly recommend this company. I will be continuing to call on them. read more

These guys are absolutely the best in the business - hands down!!! Brian and his crew are the fastest, courteous and most reasonably priced in Longmont. Two weeks ago, our A/C unit stopped working right in the middle of arriving guests for a wedding. Called Brian and they were on the job the very next day. Right on time, fixed it like new and even found that the original installer had wired the fan motor incorrectly. When I got the bill I couldn't believe how inexpensive the service call was. I honestly would have paid twice that amount for the superior service and quick response. I would recommend highly!!!! read more

I was fortunate to find a honest, cordial, clean, and reasonable furnace repair person. The repairman showed up within 5 minutes of appointment which is fantastic for repair people. It isn't uncommon to have repair people show up an hour or longer late or not show up at all. He gave me a price over the phone and the amount he charged is what he told me. He repaired the problem and my furnace was working afterward. I would do business with him again. I had other repair people called me back with a price starting, on a weekend, from $200 to $300. Also the BBB gave him an A without being a member without any complaints. It is a lot harder to get a good rating if you aren't a member. read more

Brien's courteous staff installed a LG split cooling system last week. The cost was reasonable. The work was prompt and professional. We have a winner! read more

I wish There were 6 Stars to give. Brien at Carroll Mechanical Services did a complete HVAC installation in a rental property destroyed by Meth Contamination. They completed the extensive job quickly, when promised, and with high Quality. Obvious deep experience and talent here. Probably the singularly best contractor experience I have ever had, start to finish. read more

If I could give ten stars I would. Andy was great and clearly knew what he was doing. CMS was the third company I called about our Rheem RTG-74DVN-1 tankless water heater. The water heater was shutting down mid shower more and more frequently and throwing an error code to call a technician. Precision Plumbing wanted $1,300 to service it and said they couldn't be sure the service would eliminate the problem. Their recommendation was to replace the unit altogether at a cost of over $6,000. Flatirons Plumbing made the same suggestion while pointing out at least one error in installation that turned out not to be an error at all. Neither company did more than take the cover off of it and troubleshoot. My guess is that neither company sells Rheem tankless heaters and instead of just saying they don't service them, they tried to sell us a new one. When Andy showed up, he'd clearly worked on this model before and said that it wasn't well designed in terms of access for servicing but was very doable. He answered all my questions, serviced the unit beautifully (which did require pulling it apart) and charged us $170. I will never call anyone else again. Thank you Andy! read more

Our AC went out on the hottest day of the year! Called Brien on Father's Day (hated to do it!) He came out promptly the next day. Unfortunately he needed to replace the whole unit. He gave us an excellent price and did a great job on the install. He's very knowledgeable, professional and prompt. We wouldn't ever call anyone else! read more

Just had Carroll Mechanical come over for the 2nd time, this time for a furnace check. As usual, their technician was nice, patient, quick and knowledgeable, and even wore booties out of respect for my hardwood floors and carpet. And I just found out they replace water heaters, so when mine goes, I will call them to replace it. Thanks as always, Great Job! read more

I just had an air conditioner and furnace installed by Carroll Mechanical. I have to say this is the best company I have ever worked with. The crew was outstanding, the work was excellent and the price was very fair. I would recommend Carroll to everyone! It was such a pleasure to hire a company that does what they agreed to do!!!!!!! If you want the best, call Carroll Mechanical....you won't be disappointed! read more