Data Center Horror Stories: 5 Cooling Myths That Refuse to Die
Welcome to Keep Your Cool - a blog about simple cooling optimization strategies for the busy data center operators.
Every data center has its ghosts — old ideas that linger long after they’ve stopped being useful. This Halloween, we’re busting five of the most persistent myths about cooling and airflow that continue to haunt operators and engineers.
Because in a world of rising IT loads, GPUs, and mixed cooling strategies, the scariest thing isn’t a ghost. It’s a blind spot.
Myth #1: If it feels cool, it’s okay.
Walk into a cold aisle and you’ll probably feel a nice breeze — but that doesn’t mean your servers are happy. Human comfort and IT airflow are two very different things.
Localized cold spots can hide nearby hot zones, especially in legacy halls or partially contained aisles. Without rack-level temperature monitoring, you’re guessing.
Reality check: Use distributed sensors (or an AUDIT-BUDDY) to measure temperatures where it matters — at the server inlet, not your elbows.
Myth #2: You can’t overcool a room.
Too much cold air sounds harmless, but it’s not. Overcooling increases fan energy, wastes chilled water, and can disrupt containment balance.
Worse, excessive supply pressure can actually create bypass airflow — cold air that never reaches the servers at all.
Reality check: Optimize, don’t overcompensate. A small increase in supply temperature can improve efficiency and stabilize airflow, especially when paired with good containment.
Myth #3: Sensors near the CRAC tell you everything.
They don’t. The further air travels from the CRAC, the more it mixes, stratifies, and behaves in ways you can’t see from one or two points.
Reality check: A handful of sensors can’t capture what’s happening rack-to-rack or top-to-bottom. That’s why thermal surveys or Dynamic Heat Maps are so valuable — they show the real airflow pattern, not just the averages.
Myth #4: Liquid cooling will solve everything.
Liquid cooling is gaining ground, especially in GPU-heavy environments, but it’s not a silver bullet. Hybrid facilities will still depend on traditional air systems to manage residual heat and room balance.
Reality check: You can’t abandon airflow management just because part of the load is liquid cooled. Validate both systems together — how one behaves affects the other.
Myth #5: If there are no alarms then everything’s fine.
Silence isn’t safety. Many facilities operate on the edge of their cooling capacity without realizing it. Without trending, visualization, or periodic assessments, small inefficiencies can grow into big risks.
Reality check: If you only check when something breaks, you’re already too late. Schedule periodic airflow assessments or deploy AUDIT-BUDDY for spot-checks to catch subtle shifts before they cause downtime.
The Final Scare
Cooling myths persist because they often used to be true — before workloads changed, containment improved, or density skyrocketed. Today, data centers evolve faster than rules of thumb can keep up.
The good news? You don’t need to guess. With tools like AUDIT-BUDDY and Dynamic Heat Maps, you can see exactly how your airflow behaves — and exorcise inefficiencies before they come back to haunt you.
About Purkay Labs
Purkay Labs provides practical tools and services to validate cooling and airflow strategies in operational data centers. Our flagship product, AUDIT-BUDDY, is a portable rack-level temperature and humidity monitor used for spot-checks, commissioning, and troubleshooting. Using our AUDIT-MATE software, we help operators visualize, analyze, and optimize airflow — from hyperscale halls to UPS rooms.
👉 Schedule a free 30-minute consultation with Purkay Labs’ thermal experts to discuss your next scariest issue.