Online Reviews



 Larry Eggers

“We cannot say enough about the excellent care and service that Mark Palmer and his company has provided for us on so many occasions.  We have called them for servicing our HVAC system, new hot water heater replacement and various electrical work!  I’ve always said, “if a contractor in the Valley would just return a phone call and show up, they would be crazy successful”!  Well not only does Mark return phone calls and shows up when he says he will; they provide unbelievable professional service.  Everything from putting “booties” on their shoes to cleaning up after they complete their work; it is done with the highest level of care!  We have had contractors in many of our homes over the years and we have put up with unprofessional services, rude behavior, even cursing and complaining about their work.  Not with Great Northern!  If you are looking for honest, kind and professional service; this is the company for you.  We cannot say enough we are “raving fans”! 

Kimberly Bridwell 

 “I was so grateful for Great Northern Heat and Air company when I  found myself without heat in the dead of winter. My husband was of  course out of town because that is when these things tend to happen.  Mark at Great Northern responded immediately and had our home warm and  cozy in no time! This positive experience with prompt and excellent  customer care convinced us to purchase our air conditioning system with  them.
Again they were so accommodating, professional, and the work was top quality! We would highly recommend this excellent company!

Debbie Cook 

Mark and GNHA, did an outstanding job recommending and installing  our Fujitsu mini split units. We were more than pleased with the  professionalism and quality of his work. He was very clean, tidy and  organized which made the install quick and painless. The savings we’ve  seen with the new units was also amazing, thank you GNHA.  We’ll  definitely call on you for all our heating and air conditioning needs!

Jesse Moore 

 "Nothing  but professional! Mark and the team at Great Northern Heating & Air  are top notch. They were prompt when responding to our need for  service. Excellent customer service and quality work...I would highly  recommend these guys!"

Patrick Huelman, Associate Extension Professor & Cold Climate Housing Coordinator

​It is my pleasure to write a testimonial for Mark.  A highly skilled and conscientious HVAC contractor can be a hard thing to find.  There are three things that set Mark apart from others in this field.  
1) He is extremely knowledgeable across a wide variety of HVAC system types.
2) He listens carefully to what the customer wants to achieve.
3) His vast and varied experience allows him to develop a customized solution to exceed the customer's needs.   

Our University of Minnesota Cold Climate Housing Program has encountered several unique and demanding HVAC research and demonstration projects.  Mark was always our first choice.  He would listen intently to our concerns and needs.  Then he goes to work to deliver a high-performance solution.

Jon Foust, Director of Marketing, Roxbury Capital Management

We hired Mark based on a personal recommendation from our contractor to review and upgrade our existing furnace/air conditioning units at our home. Mark impressed us with his thorough understanding of our needs and delivered an incredible cost effective solution that overcame some significant obstacles. Mark was timely, efficient and a pleasure to work with throughout the process. We would highly recommend Mark to all of our friends.

Tom Grailer, Principal Scientist at Medtronic, Inc

I recommend Mark and his company, Great Northern Heating & Air. For your residential HVAC needs. He has provided prompt, professional service when needed since 1998.

 Mark Henning, Principal Software Engineer at ITT Industries

I have had Mark repair our whole home boiler / domestic hot water on two occasions. He has always been completely professional and is willing to explain the details of the problem and be certain that I understand what it will take to solve the issue.

Dennis Rust, Sales Executive

Mark is always on time and does a great job at a reasonable cost for all types of air conditioning and heating issues. He has repaired/replaced my furnaces and air conditioning units as well as my friends units and everyone is very impressed and satisfied by his work.

Mike Jindra, Outside Sales Rep. at Dakota Supply Group

Mark is a very honest hard working HVAC professional. He has a very good perspective on how each house works as a total system. We have recommended Mark to several homeowners, who always give us outstanding feedback on his workmanship and positive attitude. I am fortunate to also be able to call him a friend.