John O’Reilly

John O’Reilly has devoted his entire professional career to the design and construction industry — particularly plumbing and HVAC. Before entering the agency business in the mid-1990s, John worked for over 20 years as an editor with Supply House Times, developing business management content on and for plumbing and heating wholesaler-distributors. That professional background eventually brought him to the attention of a suburban Chicago-based agency that served building-product manufacturers. O’Reilly joined the agency in 1996, purchased it from the founder in 2004, and eventually re-branded it as GreenHouse Digital + PR.

O’Reilly can be reached at john@greenhousedigitalpr.com.

Six tankless water heaters that feed the nutraceutical manufacturer’s operations.

Case Study

How to deliver large volumes of hot water quickly and intermittently

California-based nutraceutical manufacturer meets large, spiking hot-water needs with a combination tankless-and-tank system.

John O’Reilly

May 13, 2025

Proper water heater sizing in any application hinges primarily on user consumption within a given period. That much is probably obvious, even to someone who has never sized a water heater. What complicates matters, especially in a large commercial application, is the cadence of that usage.

17-unit, Noritz tankless water heater system at Wedgworth’s fertilizer blending facility in Lake Placid, Florida

Tankless water heaters offer reliable, cost-saving alternative for fertilizer producer

Florida fertilizer producer replaces boilers with multiple-unit tankless water heater systems

John O’Reilly

September 20, 2024

Tankless water heating technology has proven to be a great success for Wedgworth's, a custom blender of dry and liquid fertilizers for agriculture, sod, nursery, and golf-course applications in Florida.

Hydronic pressurization unit helps maintain Chicago-area assisted living facility

Mikrofill 3 helps 235-unit retirement community identify potential costly leaks.

John O’Reilly

April 17, 2023

The very first installation of the Mikrofill 3 hydronic pressurization unit in North America took place recently in a mechanical room of an assisted- and independent-living community in Southwest-suburban Chicago. You might say the flower of this innovation grew from the soil of an old industry friendship.