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Dawson came out yesterday and did an awesome job. So professional and very knowledgeable!!!! Would recommend this company 100% and will be using them in the future!!!! Thanks Dawson for the work on my air conditioner!!
Karin Scott
Excellent experience with the salesman and installers. ALL of our neighbors deal exclusively with Theilmann - quality service, reliability and fair prices go a long way to create satisfied customers! I highly recommend this company!
Cheryl M
Great from start to finish. Brad provided multiple clearly outlined options while preparing the project proposal. Excellent install by Blake and Dawson. My new furnace and air conditioner look and work great. I really appreciate the attention to detail, checkpoints during the install to make sure everything was the way I wanted, spotless clean up, and final walk though of the new equipment. Thank you!
Nathan K
I have to say - I was super impressed with this company. We knew we needed an HVAC overhaul, and we knew we wanted to use Costco to get it done. Costco contracted Thielmann to come out & quote us. They were upfront, listened to my concerns, and gave us a great package that suited our needs. They scheduled an install about two weeks later, and they had it complete in about 6 hours. They did all the paperwork, dealt with our rebates & were really great to work with. I'd highly recommend!
Witne N.
I would highly recommend Thielmann & Son heating and cooling to anyone looking for installing the ductless mini split a/c units. Ryan & Dawson are so professional at what they do and are able to answer any questions you have. I agree with previous reviews, that they are top notch at what they do!!
Jeannine Thielen
These guys were awesome. It was a 93 degree day and I was having a furnace installed (only in Wisconsin) they arrived on time, went right to work and I never seen them take a break. They worked for 8 hours explaining what and why they were doing making sure everything was working before they left. I have used them for 5 yrs now and highly recommend them to everyone. The service cannot be beat.
Peter Gossen
Unbelievably great service from Brad to the guys who did the installation of furnace ac and heater in my garage very friendly and willing to answer any questions office staff as well would highly recommend this company to anybody thanks for the great job
Jim Prosen
T & Son bid against 3 other contractors for our HVAC needs. Bid was thorough, detailed and very competitive. They also provided better rebate info than their competitors. New equipment works fine. They even came out free to tweek the furnace for better performance settings. We thought the A/C was noisier than our old unit. They came out and discovered a need for some vibration insulation on the tubing mounted to our basement ceiling joists.... no charge. Techs both knowledgeable and experienced.
R Fait
These guys have been doing work for me for a couple years and I've never had any complaints. Only a defective part issue, but they were quick to resolve it for me.
Jeff Irish

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