The boiler change-out: Minnich Mechanical Design

Share With:

During the near-zero temperatures last week, the boiler change-out needed to happen without shutting off the heat. Installing a new boiler set-up while the old boiler was running took the highest level of hydronic expertise.

I knew the homeowner had nothing to worry about as soon as I met Stephen Minnich, owner, Minnich Mechanical Design, Elk Grove, Village, Ill., a 35-year veteran in the hydronics/HVAC industry.


Steve Minnich, Minnich Mechanical Design


Minnich, a proud member of the Radiant Professionals Alliance (RPA), started as an apprentice/helper in 1980 while going to trade school for HVAC/R. He quickly worked his way up to serviceman/installer and installed his first boiler in 1981. Always trying to improve his game, Steve was a Journeymen Sheet Metal Worker for Local 73 and a licensed electrician by 1987. His real passion is for radiant heating systems, boilers, all things hydronic, and has been an expert in the field for quite some time. He has also taught HVAC at Harper College in Palatine, Ill.


Minnich had to make some semblance of order out of the near-boiler piping — taken from the ceiling and reconfigured on the nearby wall.


The boiler change-out


…not to mention leaks in the old installation.

Located on the Fox River in St. Charles, Ill., I met Minnich in the basement mechanical room of this 5,000-sq.-ft home where the boiler retrofit was in mid-installation. The 12-year-old boiler had seen better days and the heat exchanger had been leaking. Minnich replaced the aging boiler with the Lochinvar Knight mod/con boiler. “The boiler features a 5:1 turndown,” said Minnich. This feature allows the boiler to generate as much or as little heat as necessary to provide a consistent, stable indoor temperature.


The Lochinvar Knight

The primary/secondary piping was run out of the Lochinvar buffer tank, which offers extended run times for the boiler. “The tank helps reduce short cycling,” says Minnich, and it is designed to provide thermal storage volume and hydraulic separation of the boiler, especially in the event that a smaller zone would call for heat.

The installation called for three zones for radiant—the master bathroom, basement and 4-car garage; and three zones for fan coils, which do not run when the boiler is not running. Grundfos Alpha pumps and Taco iSeries mixing valves aid in the water recirculation, distribution and zoning.

Previously located in the ceiling, Minnich had to reconfigure the near-boiler piping along the nearby wall.

The future of the trades


The piping is coming along nicely.

Working alongside Minnich was his son-in-law, Tim Schram. Working as an apprentice, he gains knowledge from everyday on-the-job training and taking classes at a nearby junior college, Schram is the face of the younger generation in our industry. Schram explained that he had done the college thing, graduated and ended up in a dead-end job with a boss that he disliked. He decided to give the trades a shot—with a push from his father-in-law—and he hasn’t looked back. “I love it,” says Schram. “I’m learning everyday and each job is unique.”

Minnich is ecstatic that he gave Tim a shot. “He has an incredible enthusiasm, attitude, and energy that can’t be taught,” says Minnich.



It is not uncommon to see Minnich’s mechanical drawings in the mechanical rooms.


I thoroughly enjoyed our conversation about the industry. Stephen is a great ambassador for the hydronics industry. Check out Stephen’s Facebook page or check out his website at

Join the conversation: