Design Solution · HVAC & Energy
Design Solution · Dream about it
Per-zone 4-pipe FCUs: responsive, low cost, higher maintenance.
Four-pipe fan coil units give simultaneous heating and cooling per zone with high responsiveness and comfort at low capital cost, fed fresh air into the FCU return. They carry higher local maintenance, leakage risk and need deep ceiling voids for ducted versions.
Four-pipe FCUs provide simultaneous heating and cooling to each zone independently, with high responsiveness to load change and competitive capital cost compared with chilled beam alternatives — making them the default system on a wide range of commercial office and hospitality projects. Fresh air is typically introduced into the FCU return rather than ducted independently, which simplifies the distribution but means that air quality is partially dependent on the FCU filter maintenance regime. The maintenance liability is the honest downside: FCUs have filters, fans, motors, coils and control valves that require regular access and periodic replacement, and in a multi-tenanted building the accumulated maintenance cost and disruption across hundreds of units is significant over a 25-year life. Ceiling void depth is the spatial constraint — ducted FCU configurations for deep-plan floors need voids of 500 mm or more, and in a refurbishment or constrained shell that can be the deciding factor against this system. The record carries no evidence, but FCUs are a commodity product with extensive industry cost and performance data available through standard benchmarks.
#fan coil #four-pipe #office