Zien Mechanical

Jan 2026

I’ve worked with this company for numerous years now because my landlord recommends and prefers they do the work. Never once have they came and fixed the problem they always have to come back and diagnose the issue. Don’t recommend them for HVAC. I used them from plumbing and they’re fine. That’s the only reason they got a 2 star rather than 1.

Oct 2021

I came into my building to find my boiler down. I had tried calling a few other contractors before calling Zien Mechanical as I know they were not the best on past encounters, and since I was unable to procure a service call with another contractor do to schedule conflicts, I figured I'd give Zien one more shot. Zien arrived at the designated time on time. They made the repairs as they said they would and charged me a fair price for the job. I was very impressed with their work and with the Service Manager John's quick response. I have since got on their PM program and have them maintain all my HVAC equipment. They have saved me a considerable amount of time and money while bringing other issues to my attention before they became problems. I would recommend Zien for all your HVAC needs.

May 2021

Talk about Lifesavers! I don't go out of my way everyday to write a review but these guys deserve a trophy for saving our business yesterday! We had a leak scheduled to be fixed with another plumber but they kept rescheduling us and then yesterday the leak got out of control and we had to close our kitchen an hour before the lunch rush. We got on the phone and called every plumber in Milwaukee and Zien was the first one on the scene. Their guy was super fast and fixed the problem in about 20 minutes and we were back up and running serving lunch! Thank you Zien!