Proudly serving The Northland since 1934

Trusted HVAC & Plumbing Professionals

For nearly 90 years, servicing and maintaining the arteries of your building or home has been the mainstay of our work.

Installing, replacing, repairing, and maintaining your plumbing, heating, cooling, and HVAC systems is our purpose. At A.G. O’Brien, we build trust through transparency and competence. Being available when you need us the most and making sure you understand what we are doing, how we are doing it, and why. We install the best products and can repair just about anything else.

“Respect is earned
Honesty is appreciated.
Trust is gained.
Loyalty is returned.”

We pride ourselves in doing work that is second to none, and our portfolio includes projects for the area’s biggest businesses and community leaders.

Our Service Areas

Saint Louis County, Douglas County, Carlton County, Pine County, Itasca County, Cook County & Bayfield County.

Contact us for your FREE estimate today!