Illinois Cities Served

Durand, IL
Harvard, IL
Poplar Grove, IL
Capron, IL
Shirland, IL

South Beloit, IL
Capron, IL
Rockton, IL
Roscoe, IL

Wisconsin Cities Served

Janesville, WI   

Elkhorn, WI 
Delavan, WI 
Whitewater, WI 
Fort Atkinson, WI 
Milton, WI 
Edgerton, WI 
Macfarland, WI 
Madison, WI 
Evansville, WI 
Orfordville, WI 
Darien, WI
Beloit, WI

Lake Geneva, WI
Mukwonago, WI
East Troy, WI
Lake Mills, WI
Brodhead, WI
Monroe, WI
Deerfield, WI
Oregon, WI

Evansville, WI 
Albany, WI
Juda, WI 
New Glarus, WI
Jefferson, WI
Johnson Creek, WI
Stoughton, WI
Cambridge, WI
Walworth, WI


Clay -

Thank you for doing a great job in keeping Fletcher and me warm and toasty. Not all heating-cooling companies are as trustworthy as Don-Martin Heating. 


Dear Clay:

My husband and I would like to extend a big thank you for all the work, technical support, and help that you and your crew have provided us over the past several months. 

In the fall of 2009, we installed two separate geothermal systems at our residence; one system for our house and another for our workshop which utilizes radiant floor heating.  We began the process by obtaining numerous quotes.  After extensive research and consideration comparing cost, technical knowledge and reference checks we opted to utilize Don-Martin Heating for our project and have no regrets. 

Clay and his staff are “top-notch” responding to all our needs and requests.  They continue to work through situations eliminating any concerns and meeting all expectations. They always get back to me timely and keep me abreast of the schedule. As part of the full service support, Clay also helped complete local rebates and information for tax incentives providing a complete turn-key service.  Clay has demonstrated through his work to be very professional, courteous, knowledgeable and trustworthy.  He has provided much needed advice at all stages throughout the entire process (initial quote, installation, and post installation). 

I would highly recommend using Don-Martin heating for all your heating and cooling needs.  Their service is great and we know we can count on them at any time and into the future.  I have already recommended Don-Martin to family, friends and colleagues.  Just recently my brother utilized Don-Martin services to install an air conditioner.  This also proved to be another cost-effective job well done. 

Thanks again,

Julie Mosley


I really appreciate your service and help. 


Dear Mr. Kohlhagen,

This letter is to thank you and all your employees that took part in the installation of the geothermal system installed in our house. We entered into this project with some trepidation, but our fears were unfounded as the results have shown. you were timely in evaluating our home, and provided a timeline for installation process. Within several days of making our selection, the project began with the installation of the ground loop system. A week thereafter your employees appeared at 7:00 AM as promised. The tear out of our old heating and air conditioning units and the completed installation of the geothermal unit, the hook up and the ground loop, and the installation of the hot water receptacle tied into out hot water system were all completed that same day. 

Very rarely in my life have vendors lived up to either of their claims for their products or the quality of the workmanship. In this case that is exactly what occurred. All work was done precisely on time with qualified and professional employees who have indeed lived up to your promises in every respect. 

Thank you so much for your efforts and the quality of your products and workmanship.


Shirley Daley & Family


Just to let you know how pleased we are with our geo thermal Water Furnace. After 1 year of use the unit has used $274.06 worth of electricity over the previous year. This is for heating and cooling. With our old system we would have used 700-800 gal of propane at $1.44/gal ($1000-$1150) plus the cost of air conditioning ($120). Our total savings for the first year is close to $1000.

With cost of propane going up every year, our Water Furnace will pay for itself in 8-10 years.

We actual kept the house 2 degrees warmer in the winter and 3 degrees cooler in the summer then we did with our old system, so the savings could be even greater than this. The heating and cooling is more even with fewer cold spots next to windows or walls in the winter. With an older house like ours this is a great improvement.

We were also pleased with the installation of the Water Furnace. Everything was neatly done and looks great. It fits in the footprint of our old furnace without looking like an add on unit.

I am attaching actual usage of electricity and graphs showing average temperatures over the first year.

Levi & Jackie Olson 
Whitewater WI

Thank you!

In 13 years no one has ever been able to offer a solution to the noisy fan - until you!



This is just a note to thank you for getting my mothers furnace replaced so quickly. I also appreciated the reasonable price you charged. The guys did a nice job! 

Thank you.


Cindy Prunell

​​Wisconsin Counties Served 
Rock County, Wisconsin
Walworth County, Wisconsin
Dane County, Wisconsin
Jefferson County, Wisconsin
Green County, 



heating, air conditioning, Geothermal & Indoor air Quality Contractor Meeting the  needs with OVER 40 years