Problems with critical cooling can include fluid leaks, dirty/clogged filters, worn belts & bearings, failed sensors, clogged condensate drains, and control sequences that are not fully automatic.
1. A faulty sensor should be alerted as a missing data point. But it may inconspicuously provide faulty readings. Many sensors are submerged in closed loop circuits where fouling and scaling can develop. Maintaining water quality reduces sensor misinformation and failures.
2. Water filled hydronic piping has failure risks. Automatic control and isolation valves sometimes get stuck with no feedback provided. However, stuck valve conditions can be deduced in other ways, such as from flow sensors on the air handling equipment. Leak detection system performance is more important with limited onsite staff. Detection should be located close to the source (hydronic piping, secondary drain pans, etc.).
3. Pay attention to air side economizers, regularly changing out filters and monitoring pressure differential sensors. Keep filters from becoming loaded, which could introduce pollutants into the facility and reduce fan coil life expectancy.
Unfortunately, pandemic stresses may require less use of existing economizing features due to their complexity and may result in delays or cancellation of planned energy efficiency upgrades. But planning, budgeting, and at least conceptual design should continue for more timely action in the future.
Michael Fluegeman (mfluegeman@plannet.com), PE, is director of engineering and principal, critical facilities, for PlanNet, an independent professional services firm that provides advisory, design, project management, and construction services supporting critical IT infrastructure.
Antonio “Tommy” Tan III (ttan@plannet.com), PE, is a critical facilities mechanical engineer at PlanNet.
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