A Pragmatic Approach to Equipment Cooling in Exhibits
Who knew it mattered? Well, looking after equipment is important if you consider that for every 18°F (10°C) rise above normal room temperature (72°F, 22°C), the life expectancy of electronic components is effectively halved. That is not theoretical. It is well-established reliability behavior driven by thermal stress on semiconductors, capacitors, and power supplies.
And yet, equipment cooling is one of the most commonly overlooked aspects of exhibit and show design, especially when computers, media players, and monitors are built into sealed or semi-sealed setwork.
This article is not about complex thermal modeling. It is about applying practical, common-sense engineering that avoids failure.
Many systems end up with someone installing a fan inside a cabinet, assuming that "moving air around" will solve the problem. It does not. A fan inside a closed volume simply redistributes heat. It does not remove it. Without a defined path for heat to leave the enclosure, temperatures will continue to rise until something fails. As a thought model, imagine putting a heater into a box, and using a fan inside to stir the air — it doesn't actually do anything to remove that air, so the temperature will just go up.
That brings us to a more subtle but equally critical mistake: trying to "suck" hot air out of a cabinet.
At first glance, extracting air seems logical. Remove hot air, and cooler air will replace it. The problem is control. When you pull air out of an enclosure, you create negative pressure. That means replacement air will enter from wherever it can — gaps, cable entries, seams, unsealed joints. You have no control over the source, the path, or the quality of that incoming air.
In practice, this leads to several problems. You may pull in warm air from adjacent cavities or ceiling voids, which defeats the purpose entirely. You may pull in dust, fibers, or contaminants that will accumulate on heat sinks, fans, and circuit boards, reducing cooling efficiency over time. You will pull in air past other components through cracks — where monitors are not perfectly sealed, through speaker holes, through other cracks and holes in the setwork. That results in dirt streaks as it moves dirty air at higher speeds into the cabinet, causing static buildup as it happens. You create unpredictable airflow paths, which means some components get cooled while others sit in stagnant hot zones.
In other words, extraction alone is not a cooling strategy. It is an uncontrolled gamble. And remember that hot air rises — so even if you do pull air out, pull it out of the top. Pulling air out of the bottom creates an additional problem: a potential hotspot at the top of the cabinet.
You need to push clean, controlled air into the cabinet from below — cool air enters low, it rises as it heats, and exits high.
By slightly pressurizing the enclosure with filtered, ambient air, you define exactly where the air comes from and where it goes. You create a known airflow path across the equipment, from intake to exhaust. You ensure that every component sees moving air, not just the ones near a fan — and the air in the cabinet is always clean for optimal equipment longevity.
Positive pressure also prevents dust ingress, because air leaks outward rather than inward. That alone can significantly extend system reliability in real-world environments like museums, visitor centers, and trade shows. Adding internal baffling to direct the air along the best possible path, and you have a solution that allows for the best possible equipment life.
There is one more critical point that is often missed, even when intake and exhaust are both present: you must prevent airflow "short-circuiting."
If the exhaust air can find its way back to the intake, even partially, you are effectively cooling the system with its own waste heat. This happens more often than people realize, especially in tight cabinetry or poorly partitioned setwork.
Typical causes include: intake and exhaust vents placed too close together; no internal baffling to separate cold and hot zones; air taking the easiest path rather than the intended path across components; and recirculation within ceiling voids or enclosed scenic structures. When this happens, temperatures rise even though fans are running, and it can be very difficult to diagnose because airflow appears to be present.
A proper design must enforce separation. Intake air enters on one side or zone, always low. Air is forced across the heat-generating equipment. Exhaust air exits from a different, isolated location. Cross-flowing air is often a good solution — input left low, output right top. Physical barriers or ducting prevent any mixing of hot exhaust and cool intake air.
It is fine to add a suction fan — but aim to have suction be less than the air being pushed into the cabinet. A positive air pressure differential inside the cabinet is a good thing.
If you cannot guarantee that separation, you do not have effective cooling, no matter how many fans you install.
Controlled intake. Bring in clean air from a known source, ideally filtered, at ambient room temperature.
Defined airflow path. Direct that air across heat-generating components, not randomly around the enclosure.
Managed exhaust. Provide a clear exit path for the warmed air, so heat is actually removed from the cabinet. Most of the time, an exhaust fan is not necessary if the leaks in the cabinet are reasonably contained. Measure flow and temperature — or at minimum, feel the airflow from the intended exhaust — and make sure there is enough flow to limit heat gain inside the cabinet.
No recirculation. Ensure that hot exhaust air cannot re-enter the intake stream under any circumstances.
If you do not have all four, you do not have cooling. You have wishful thinking.
The goal is not complexity. It is control. There is some solid, simple-to-implement advice here that will help your clients avoid premature failures, reduce maintenance, and protect their investment.