Reduce Boiler Fuel Consumption by 50 Percent

The life blood of any commercial building is the mechanical systems running behind the scenes that include domestic water booster systems, fire suppression pump systems and HVAC systems.

Of the three mechanical components, HVAC is by far the largest consumer of energy due to the sheer nature of how they are specified and designed. The school of thought in the HVAC community is size everything for peak demand without considering demand fluctuates, especially during warmer months when demand is at the lowest.

The biggest misconception when specifying a boiler system is, “If I specify a boiler at 90% efficiency then the plant will operate at 90% efficiency.” This is false because during light load conditions, such as during warm months, boiler efficiency becomes random which results in poor overall, “cycle” efficiency. In other words, “Seasonal Efficiency,” is only 50-80% of measured efficiency resulting in no realized energy savings during the warm months when your boiler runs less.

Metropolitan Industries, Inc., located in Romeoville, Ill., has a solution that reduces boiler fuel consumption by 20-50% using a patented procedure that addresses seasonal efficiency, which increases cycle efficiency therefore reducing fuel consumption dramatically.

Case Study – Multi Occupancy Condominium

A great example of this technology was demonstrated by the work done at a 139 unit Condominium located in Will County, Ill. At the request of the owner, the building name and location of the project is to remain confidential.

The existing system had two problems the first being the plant ran inefficiently due to the boilers being the sole heat source for the domestic water. Due to this, they operated all year round, even during the summer months. The inefficient design operated by pumping city water and boiler water through a shell and tube heat exchanger mounted near the ceiling. Since there was no way to prevent gravity flow of hot water through the heating system return lines, the radiation caused the building to stay warm all year, even in the dog days of summer. This resulted in increased fuel consumption and increased electrical consumption as well because air conditioners witnessed an additional load imposed by the uncontrolled flow of unwanted heat from the boiler plant and needed to run overtime.

The second problem was the existing heating pumps were leaking and had been since day one. There were eight zone pumps serving four zones. Three zones were for space heating and the other zone for domestic hot water heating. The reason why they leak was because they were mounted near the ceiling without the proper supports. This made it difficult to service the pumps given a technician need to perform the work on a ladder.

Green Performance Solution

To solve the inefficient operation of the plant, Metropolitan Industries installed a “summer boiler,” sized to the requirements of the domestic hot water heating system. This allows the owner to turn off the boiler completely when a heating load is non-existent. The result is energy savings up to 50% because the new boiler system handles the small summer loads efficiently and eliminates short cycling and cycle losses.

The summer boiler is so efficient that the owner can run it year round for more efficient domestic water heating meaning the building can now be heated with only one boiler in all but the most severe weather promotes more efficient boiler loading for improved energy performance.

Green Distribution Solution

To address the issue of the leaky heating pumps, Metropolitan moved the domestic water heat exchanger and blending valve to floor level for easier inspection and

service Workers no longer needed to climb on ladders when servicing the heat exchanger or blending valves. This not only improves staff and contractor safety but reduced maintenance costs overall due to the easier and less expensive service.

One of the biggest benefits is the control over domestic hot water temperatures. No longer will they have spikes or drifts of temperature irregardless of no load or light load conditions. The elimination of spikes in temperature was important given residents were at risk for being injured.

There were benefits as well with the relocation of the heat exchanger and blending valves to the floor. For one, it reduced the safety hazards associated with working on ladders when servicing the heat exchanger or blending valves improving contractor safety.  Also with the new pumps, the constant leaking was eliminated.

Realized Energy Savings

With the installation of the “summer boiler”, new heat exchanger and blending valve, the building owner realizes a 20-50% reduction in fuel consumption on any given day depending on load conditions. The entire package combines indirect water heating, condensing water heating and the blending valve function all into one complete system. Metropolitan Industries is the only company currently providing this technology. For more information, contact Matt Brickey at 815-886-9200 ext. 266 for a complete analysis of your system.