By Luke Wonnell Besides being a wicked awesome band name, the title of this article refers to some 201 level Thermodynamic principles that have a significant impact on the performance of your steam boiler. “Heat flux” defines how much heat transfer occurs through a given material’s surface area and is expressed in (Btu/hr-in2 or W/m2). Think […]
By Luke Wonnell If you’re like me then you remember learning in High School chemistry or pre-req college courses that water has 3 states: solid, liquid and gas right? Water becomes solid ice below 32⁰F, exists as a liquid between 33⁰F and 212⁰F and starts to boil off to a gas at 212⁰F. While these […]
Modern HVAC design often employs a wide selection of metals which are used in system components and transmission lines. New construction specifications require protection for systems comprised of steel, copper, bronze, stainless steel, galvanized and even aluminum. In most cases, multiple metals are usually present in any given system. In addition, some component suppliers specify/demand […]
Glycol systems present Facility Managers with a host of new challenges and opportunities. Protecting systems from freezing in cold weather climates is critical. However, glycol can behave very differently and requires that water system conditions be carefully prepared in advance. Without attention to detail, these systems can produce unwanted headaches. Dealing with fouled glycol systems […]
What Exactly is a British Thermal Unit (BTU)? By Luke Wonnell Oh the Imperial system… home to such gems as hectares, stones, bushels and pints. Personally I’m a fan of that last one, especially when served cold. The Imperial system is very finicky: 12 inches to a foot, water freezes at 32⁰F, boils at 212⁰F, […]
Presence of the Legionella organism in water systems can often be associated with the presence of biofilm. Biofilm is a sticky substance which forms under the right conditions, often appearing as slime. It attaches to piping and component surfaces, and provides the ideal environment for a community of organisms, including Legionella, to live and thrive. […]
How does Water Treatment result in Energy Savings for my Building? The primary functions of a Chemical Water Treatment program for heating and cooling systems that use water as a heat transfer medium are the control of scale, corrosion and micro organisms. Left untreated, water will cause scale or mineral deposits to form on heat […]
Updated HPD Heat Season Requirements By Luke Wonnell On Monday, October 2nd, 2017, NYC Housing Preservation & Development released new requirements which were made effective for the start of the 2017-2018 heat season. This release included specific changes to the nighttime heating requirements: The law requires that from October 1 to May 31: Between 6:00 […]
Cooling tower overflow is a subtle, yet costly problem which often goes unnoticed. The challenge is more pronounced during colder weather when heat rejection and evaporation requirements tend to be lower. The primary purpose of the cooling tower is to reduce water consumption. Overflow obviously defeats this purpose by robbing those savings. The problem can […]
What Exactly is Boiler Horsepower (BHP)? By Luke Wonnell In the United States, the output capacity of steam boilers is expressed as Boiler Horsepower (BHP) whereas hydronic boilers are typically sized based on their input capacity in Btu’s/hr. There are definite differences between these two methods, but it is possible to convert between the two units of measure. 1 […]
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