Balancing valve

A balancing valve sets the flow rate of chilled water through an FCU or a branch of the chilled-water loop. It doesn't switch flow on and off — that's the two-port valve — and it doesn't filter debris — that's the Y-strainer; it throttles the flow to the right amount so every unit in the building gets its fair share. Get it wrong and you get the classic 'this one room never cools properly' complaint: a balancing valve throttled too far (or never commissioned properly after a fit-out) starves that coil of flow, so it under-cools even though the two-port valve opens, the strainer's clean and the central plant is fine. The opposite also bites — one unit left wide open can steal flow from the rest of its riser and starve its neighbours. Proper balancing is a commissioning job done with flow measurement across the whole system, not a valve you nudge by feel, which is why persistent single-room or single-riser cooling problems are best handed to Al Ghubaiba's water chiller team rather than cracking valves open at random.