Description

During the peak of a heating season, a client had an issue with one of their institutional buildings – the Water Source Heat Pumps (WSHPs) that were supposed to provide supplemental heating were cooling the spaces! The client initially thought the Heat Exchanger (HX) serving the system was corroded and blocked and received bids for replacing the HX. Before proceeding with this work, the client asked BEC to review the issue. BEC performed functional testing on the system and discovered that an actuator that operates a crucial valve had failed. In the failed position, the water from the building WSHPs were flowing to the cooling towers instead of the boiler HX; I.E. it was stuck in cooling mode instead of heating the building. BEC was able to manually operate the valve, allowing water to flow through the HX and allowing the WSHPs to provide the much-needed supplemental heating. BEC commissioning tests confirmed that the corrective measure was to repair the actuator. BEC correctly diagnosed the problem and saved the client from spending considerably more (10-20X the cost of the simple actuator repair) on a HX replacement that would not have solved the problem.

Description

BEC performed Retro-Commissioning of the boiler plant within Franklin Square Apartments, a 193-unit senior housing facility. The boiler monitoring system had alerted the facility to issues with the operations including short-cycling of two of the four boilers. BEC performed functional tests for each boiler and deployed multiple data loggers to monitor the system operation. BEC’s investigation revealed three critical performance issues: 1) the two boilers that were short-cycling had under-sized pumps that could not provide adequate flow. Inadequate flow through the boilers caused the boilers to shut down on high temperature alarm, 2) the controls were not cable of operating the four-stage modulating boilers as modulating boilers, and 3) one boiler had a fault in the control wiring. These issues were compounded by the fact that the building loop pumps did not incorporate warm weather shutdown (WWSD) or variable speed (VFD) control. BEC developed a corrective plan for the boiler plant and is guiding the owner through implementation of the project.

Description

Billings Forge is a complex of former mill buildings that have been converted into residential
units. There have been renovations and modifications over the years, some that have made
improvements to the operations. Problems with heating adequacy and distribution had been
persistent despite multiple assessments, installation of new boilers and pumps, and attempts to correct central boiler plant issues. BEC performed Retro-Commissioning (RCx) of the central
boiler plant, data logged the operation, and assessed the distribution and specific enclosure
components. BEC found that the piping configuration had considerable flow restrictions and
pumping issues which caused one building to receive most of the heat while the other buildings were lacking. Also, one of the two boilers provided nearly all of the heating capacity while the other boiler short cycled every few minutes for the entire heating season. BEC developed a plan for modest modifications to the pumping, pipe configuration and controls that allow the boilers to function in coordination and provide effective delivery of heating to all buildings within the complex. BEC is currently overseeing the design-build implementation of this plan on behalf of the owner.

Description