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42U > Knowledge Base > Newsroom & Blog > Infrastructure Solutions > Airflow Management > Are Blanking Filler Panels the best, low-cost solution for your cooling needs?

Are Blanking Filler Panels the best, low-cost solution for your cooling needs?


Upsite Blanking Panels

Seal rack openings with HotLok Filler Blank Panels (often spelled: HotLock)

The Upsite HotLok Blanking Panel is a snap-in blanking panel that provides a 99.97+%+ effective seal in IT equipment cabinets. The state-of-the-art technology, designed for both 1U and 2U openings, controls airflow for optimized cooling effectiveness.  HotLok Blanking Panel is Upsite’s latest green solution for energy savings and reducing the carbon footprint of data centers.

Both 1U- and 2U-configured versions achieve the following:

  • Reduce hotspots and bypass airflow by preventing equipment exhaust air or hot-aisle air from migrating to the conditioned air-intake stream at the front of the cabinet
  • Deliver lower temperature conditioned air to the upper one-third of the cabinet, typically the hottest area and most prone to equipment failure
  • Control airflow to save energy by adjusting cooling unit setpoints

Data center managers can optimize the cooling capacity of their computer rooms using the most effective sealing blanking panels available. HotLok Blanking Panels are often misspelled HotLock Blanking Panels. The HotLok Blanking Panel design combines the following features and benefits:

  • Engineered to provide the most effective seal available for optimized cooling capacity within a server cabinet
  • Designed with inboard ergonomic finger grips for easy, quick, safe, tool-free installation that saves on labor costs
  • Stackable, so they can be kept on hand in a particulate-free storage environment
  • Made of lightweight plastic material to lower shipping costs
  • RoHS- and UL-certified, and both product and package are recyclable

The HotLok blanking panels are also available with an attached temperature strip.  The temperature strip identifies temperatures within a particular range, accurate to within +/- 1° C:

  • Blue: Optimal Operating Range based on recommendations from ASHRAE
  • Yellow: Acceptable Operating Range based on equipment manufacturers’ recommendations for Class 1 IT equipment
  • Red: Outside acceptable operating range, indicates a definite hotspot or potential for condensation, either of which may result in equipment damage or failure

Are Blanking / Filler Panels the best, low-cost solution for your cooling needs?

Key Features:

  • Snap-spring design offers durable, 99.97+% effective seal.
  • Tool-free, snap-in installation and easy-pull removal for any EIA-310-E standard openings using ergonomically designed finger grip.
  • Cantilevered sealing vanes eliminate the gap between adjoining Blanking Panels or with installed equipment.
  • 1U Panels stack 10 high and 2U Panels stack 20 high for easy storage and ready availability.
  • Upsite Temperature Strip colored-coded temperature ranges indicates potential hotspots by color based on ASHRAE Standard.


  • Use 1U and 2U versions on cabinets with standard 19-inch rail widths (483 millimeter).
  • Use with any standard EIA-310-E openings.
  • Use in a Hot and Cold Aisle layout for low or high heat density cabinets.
  • Use in existing cabinets for optimization and standardization.
  • Use version with Temperature Strips to determine the temperature at that position in the cabinet or install throughout to determine the range of temperatures from the top to the bottom of the cabinets.

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