Readers flocked to PM Engineerthis year for the latest information on new products and technologies, industry news and market trends. Here’s a countdown of the top 10 articles you read the most in 2022 based on the number of unique pageviews on

10. Spot check on the commercial water heating market
The commercial water heating market has options for building owners and facility managers when it comes to selecting equipment for their facilities — tank or tankless, gas models or electric — even heat pump water heaters are seeing growth in this space. So which is the most popular? Well, it all depends on who you ask.


9. Julius Ballanco: Decarbonization and electrification — are we there yet?
Decarbonization and electrification are buzz words passing through the engineering profession. Some consider these two words to be one and the same. However, that is not true. Decarbonization simply means a reduction in carbon, thus the reduction in carbon dioxide generated during combustion. Electrification is the use of electricity for power. Hence, electrification is one means used to attain decarbonization.


8. Dave Yates: Why 120F is not a safe water temperature for potable water storage vessels
When I first entered the trades in 1972, residential tank-style water heaters shipped with the aquastat set to approximately 140° F. Dishwashers had no need to incorporate a sanitizing cycle. Around 1977, water heater manufacturers were required to lower the aquastat temperature setting to approximately 120°, and now, dishwashers needed to incorporate a sanitizing cycle where rinse water in their reservoir was raised to 140° or higher.


7. John Siegenthaler: Heating, cooling and DHW from a single system
As global energy planning moves away from fossil fuels and toward electricity, an increasing number of hydronic heating systems are being supplied by heat pumps. Some use water-to-water heat pumps supplied by geothermal earth loops. Others use air-to-water heat pumps. Both types can supply warm water for heating, chilled water for cooling and some or all of the building’s domestic water heating load.


6. Heat pump water heaters poised for growth in commercial markets
As natural gas rates increase and the push for more sustainable energy sources intensifies, heat pump water heaters appear poised for massive growth. States such as California and Massachusetts already have regulations prohibiting or disincentivizing gas water heaters in new construction, and New York City recently enacted similar restrictions for new construction. So, are heat pump water heaters the future of the water heating market? Maybe or maybe not — but some industry experts certainly think so.


5. 2022 PM Engineer Manufacturers Rep of the Year: BDA
Every sector of the plumbing and HVAC industries is feeling the pinch of the labor shortage. However, one manufacturers rep is building a solution to the issue that has been challenging the skilled trades for years. Battersby, Danielson, Azbell, or BDA, partnered with its local community to build a brand new $16 million facility which also features a Makers Space —a 17,000 square foot vocational-technical program in which the local district sends students to learn how woodwork, metalwork, use 3D printers and more, allowing them to get the feel of working with their hands, and hopefully, entice them into a career within the trades.


4. Best practices for Legionella mitigation
There’s no doubt the plumbing industry has had a hyper-focus on Legionella and prevention over the past few years. Yet a simple search on Google reveals outbreaks in an Illinois prison, a Hawaiian hotel and in Riverside County, California — all within the past two months.


3. PM Engineer 2022 Next Gen All Stars: Top 20 Under 40 Plumbing Professionals
With all the attention given to supply chain shortages, labor shortages, inflation and material price increases, it’s sometimes hard to focus on the positives. Though the plumbing industry is aging, there are many young professionals refining and redefining their craft and making a difference. They’re bringing new ideas and strategies to overcome challenges and meet demand in their respective markets.


2. Dave Yates: Formic acid corrosion, erosion
I first encountered formic acid erosion/corrosion when our installed air conditioning and heat pump evaporator (indoor) coils began suddenly leaking refrigerant in 2008. These were not old coils either, and some had only been installed for a year when the issues arose. Most, however, were one to three years old and, unfortunately, outside of any manufacturers labor reimbursement warranties.


1. Protect CPVC and PEX pipes from harm
Over the past 60 years, plastic piping materials have evolved from a new alternative to the material of choice for building and construction applications such as hot- and cold-water plumbing distribution, fire protection and mechanical systems like hydronics and chilled water.