Hello, Our names are Jimmy and Jalene Welzig. We are the owners of Welzig Heating and Air. I started our company in 1994, along side my bride Jalene, after working in this industry for many years prior. We are family owned and operated, located in Longmont. We have made Longmont our home since 1974. We have 5 children together, Casey (1988), Cassy (1990), Wyatt (1998), Grace (2001), and Faith (2009). We incorporate trust and our high standards in every aspect of our business. I firmly believe the difference between a good company and a bad company is how they respond to the customer. At Welzig, we have developed a system with a high standard of procedures, extensive training for all our team members, and the latest technology, in order to give you, our valued customer, the highest quality customer service. Our technicians, installers, and office personnel are required to take the latest technical training, classes, and certifications. We have built our own state-of-the-art training center for our technicians and office personnel. In addition to that, Welzig provides and requires NATE certifications and factory training. Every job is unique and personalized, so we build custom fittings for your home right here in our extensive fabrication shop. All employees that show up at your home will be clearly marked in a Welzig Uniform, insured and bonded, and have the correct tools and training to complete the job in a timely and professional manor with the smile you have grown to expect. We strive to provide superior service and solutions. Cooling, heating, and conditioning the air you breathe. We’re Not Comfortable Until You Are!

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Cheyanne V.


Provided by YP.com

I have never had a problem with Welzing Heating & Air. They are reasonably priced and always, always provide assistance quickly with any HVAC needs. I have had Welzig perform furnace maintenance, replace an old hot water heater (age 11 years), and install a new furnace (former model age 17 years). Welzig techs Jason, Chris and Juan have all performed work in my home and exceeded my expectations for customer service. Talk about going the distance for a customer, Jason and Juan really outdid themselves with my new furnace!! Many thanks to the team at Welzig!

Barbara M.


Provided by YP.com

Today was my first experience with Welzig. It will not be my last. From the first contact by phone, to the prompt arrival of their technician, to the finished project, every step was done efficiently and professionally. They explained everything to me in layman's terms... and I would recommend them to all my friends and family.



Provided by YP.com

I have used Welzig for many years in different homes. No matter the install or repair, their team is always prompt, courteous and reasonably priced. There's a reason why they've been the top choice in this area for so many years: communication, customer service and fair prices.



Provided by YP.com

This company has always been reliable and extremely professional. I have had Robbie service my furnace and a/c every year and I am always satisfied. I recently had a heat pump installation and I completely believe "you get what you pay for". They were working until 8 at night to ensure I had the comfort of cool air before this hot summer sets in. I would definitely not hesitate to recommend this company to anyone for their HVAC services.


Great, fast, friendly service

We had our a/c stop working on a very warm day. We called Welzig (after numerous people suggested them). Casey their technician was here that afternoon. He was professional, courteous and friendly. We have dealt with other companies in town and found them to be efficient and competitively priced. We would definitely recommend them.


Taking advantage by Sam Holst

I wrote a review yesterday because this company tried to rip off my elderly father in law for $7900. They told him he neeede a new heating and air system. This is a follow up. Wright Heating and Air conditioning came out and inspected the air conditioner and the furnace. They said everything was in good working order. They charged him $45.


Taking advantage

We called for annual service on a residential air conditioning system. It is my father in-law's residence and he is elderly. The service technician told him he needed a new air conditioning system and a new furnace. He wasn't asked to look at the furnace. The cost was estimated at $7,900. I told him to wait and I called another company. When I told them what happenned they said. "Let me guess. Was it Welzig?" The system has received minor maintenance and is working and in good order. Welzig has a reputation for taking advantage of the elderly.


Professional job and crew

Thanks to Welzig for replacing our furnace in a professional manner. They made recommendations that worked well for us, then replaced our 10 yr old sloppy installation with a neat, compact, professional job, correcting mistakes we've lived with. Their workmen were wonderful, considerate, and professional. Their followup care has been great since Boulder had changed some code regs and they corrected the issues at no charge. Great job!!


I got what I paid for

I was in the market for a new furnace and A/C so I decided to call multiple companies to get several estimates. I decided to go with the "lowest price" bid. A technician from Welzig came out after the company that installed my new system could not fix the issues I was having with uncomfortable rooms in my house and found the the installation was completely botched and was even way oversized for my house. I decided that the money I spent on the new system wasn't worth the miserable comfort and HIGHER utility bills. The techician helped me pick the right system for my house and even gave me a discount for signing up for the maintenance plan. when the installers arrived, I could not believe how professional and respectful to my home. the installation was emaculate!!! I have never been more comfortable in my home. I was shocked when a week later they called me and came out just to make sure i was 100% satisfied and knew all of the ins and outs of my new system. THANK YOU WELZIG!!!


Very Proud Customer

Proud Customer I just built my house and we choose not to have AC installed at the time our home was built. Being a previous customer of Welzig, we opted to have Welzig come out and install our new heat pump in our new house instead of having the builders put in their builder's grade equipment. We were looking for better efficiency and higher quality. The builders were not pleased that we had an outside company come in and do the work. Welzig had to re-do the brand new duct work and flues that was put in due to poor installation from the builders. Welzig did an excellent job of installing two full systems in our house and doing it in a neat and timely fashion at a reasonable price especially for the amount of work that was put into their installation. I haven't had any problems with it, they come in annually for maintenance on our system. I highly recommend Welzig for any type of HVAC work. They went above and beyond what we were expecting and I'll never use any other company.


Exaggerates warranty to sell and then backs down - expensive.

Their cover letters when they sell talks about a 10 year warranty and when you take them up on it, they uumm and aahhh and back out of it. I would have been happy with some conciliatory discount to compensate for the misleading documentation.Also heard from several sources that you can get the same equipment and service elsewhere for less and that is exactly what I will do when I need service or equipment again.


Beware of this company

They told me I needed a new furnace. Scared me to death and told me not to even run the furnace one more time. Pressure to get the furnace in less than 1 day. Got 2nd opinion and didn't need anything even close. Stay far away from this company.


Best Service Provider I Have Ever Worked With

On time, courteous and professional. Took time to explain every issue. Fairly priced. The best experience we've ever had with any service technician for any issue in the house. Highly reccommend to any- and everyone


Poor Service, Planning, and Problem Resolution

The service representative provided misleading information and did not follow company procedures. When following up regarding problems with installation, the owner was helpful over the phone, but didn't follow through on all promises and did not respond to further inquiries.


high priced

They were the most expensive company I received a bid from


Owner Always An Answer

Thank you Welzig! Absolutely the best HVAC service in Colorado!! Very friendly, professional, knowledgable techs! The service Welzig gave me was above and beyond! I will highly reccomend them to everyone I know!

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Primary Phone: 303-678-5576

Phone: 303-485-9751

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