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Cooling Energy from Trend Logs: Weight Each Load by Its Time Interval
A cooling load reading needs a duration before it becomes energy. Timestamp spacing and logger semantics determine how each row belongs in the total.
2 days ago4 min read


Hydronic Ultrasonic Flow Sensors: Installation Checks Before Trusting Accuracy
A plausible flow reading can still be biased. Separate meter specification, installation conditions and BMS scaling with a practical hydronic commissioning checklist.
3 days ago4 min read


Estimating Chilled-Water Bypass Flow from Temperature Mixing
Temperature mixing can reveal bypass-flow fractions in a primary-secondary plant. Two worked examples show the calculation and where field measurements can mislead.
4 days ago4 min read


Chilled Water System Design Handbook: From Load to Commissioning
Explore Nexora’s 261-page chilled-water design handbook: 30 chapters covering chillers, piping, pumps, controls, worked examples and commissioning.
Sep 204 min read


How to Design Vertical Refrigerant Risers and Oil Traps
A practical guide to designing vertical refrigerant risers and oil traps, covering oil return velocity, suction pressure drop, trap placement, double risers, liquid line lift, and key commissioning checks for reliable DX and VRF system performance.
Aug 82 min read


AHU Casing Leakage & Thermal Bridging
AHU casing leakage and thermal bridging can reduce delivered airflow, increase fan and cooling energy, create condensation risk, and affect comfort. This article explains the causes, performance impact, inspection points, and practical ways to improve AHU casing performance.
Aug 81 min read


💧 Selecting Moisture Eliminators for High-Velocity Cooling Coils
High-velocity cooling coils can carry condensate into downstream ducts, filters and equipment. This guide explains how to select moisture eliminators using coil face velocity, droplet-removal efficiency, pressure drop, drainage capacity, materials and maintenance requirements. It also includes calculation methods, a worked example and practical commissioning checks.
Aug 52 min read


How to Calculate the Correct Condensate Trap for Negative-Pressure AHUs
Correct condensate trap sizing is essential for negative-pressure AHUs. This guide explains how to convert static pressure, calculate trap depth, size H1 and H2, avoid drainage failure, and prevent AHU water leakage during operation.
Aug 52 min read


AHU Drain-Pan Design: Slope, Trap Depth and Overflow Protection
AHU drain-pan design is critical for preventing leakage, standing water, corrosion, bad odor, and water carryover. This guide explains drain-pan slope, condensate trap depth, overflow protection, float switches, drain sizing, and commissioning checks for reliable HVAC operation.
Aug 42 min read


How to Select an AHU Cooling Coil: Rows, Fins and Face Velocity
Selecting the right AHU cooling coil requires more than checking cooling capacity. This guide explains how coil rows, fin density and face velocity affect heat transfer, dehumidification, pressure drop, energy use and condensate carryover. It also includes key equations, a worked example and a practical selection procedure.
Aug 32 min read


HVAC Water Treatment: Preventing Scale, Corrosion and Biological Growth
HVAC water treatment protects chilled-water and condenser-water systems from scale, corrosion and biological growth. This guide explains key risks, water quality checks, treatment methods and maintenance practices to improve efficiency, reliability and equipment life.
Aug 32 min read


Chilled-Water Pipe Expansion: Anchors, Guides and Flexible Connections
Learn how to manage thermal movement in chilled-water piping using anchors, guides, expansion loops, bellows and flexible connectors. This practical guide explains key equations, worked calculations, support arrangements, equipment protection, installation practices and common design mistakes.
Aug 32 min read
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