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Clear plastic thermostat guard with lock and wall mounting hardware

Honeywell

Honeywell sRSV-420 thermostat guard large

SKU CH-1YBC-KHWBN MPN sRSV-420

A clear lockable cover that prevents unauthorised thermostat changes while allowing air circulation and horizontal or vertical mounting

  • TypeProgrammable Thermostats
  • Prevents unauthorised temperature changes with a tumbler lock and two keys
  • Fits almost all existing thermostat models for universal compatibility
  • Mounts horizontally or vertically on a wall or exposed junction box
  • Allows air circulation through side vents for accurate thermostat operation
  • Includes clear cover, ring base, wallplate and mounting screws for complete installation

Universal Thermostat Guard Large

The Honeywell sRSV-420 is a large thermostat guard designed to prevent unauthorised adjustment of temperature settings. It fits a wide range of existing thermostat models from brands including Honeywell, White Rodgers, and Robertshaw. The unit includes a clear plastic cover, ring base, opaque wallplate, tumbler lock, two keys, and mounting screws. It can be installed horizontally or vertically on a wall or exposed junction box.

Secure Access Control for Commercial Spaces

This guard suits facilities managers and property owners who need to lock thermostat settings in shared or public areas such as offices, schools, or rental units. The tumbler lock ensures only key holders can change the program. It is not intended for installations where the thermostat exceeds the internal dimensions of 8 3/8 inches wide, 5 7/8 inches high, and 3 inches deep. Buyers needing a smaller enclosure should look at a different size.

Internal Clearance and Model Compatibility

The decisive specification is the internal cavity size of 8 3/8 inches wide by 5 7/8 inches high by 3 inches deep, which determines whether your existing thermostat will fit inside. The product lists compatibility with numerous specific model numbers including T42, T87, T8034, T8082, 1C30, 1F58, 1F90, and many others. Verify your thermostat model against the supported list before purchase.

Highlights

  • Prevents unauthorised temperature changes with a tumbler lock and two keys
  • Fits almost all existing thermostat models for universal compatibility
  • Mounts horizontally or vertically on a wall or exposed junction box
  • Allows air circulation through side vents for accurate thermostat operation
  • Includes clear cover, ring base, wallplate and mounting screws for complete installation

Specifications

BrandHoneywell
TypeProgrammable Thermostats

Questions about this item

How do I install the Honeywell sRSV-420 guard on an exposed junction box and which step is often missed?

Mount the opaque wallplate to the box using the supplied screws, pass HVAC wires through the back-plate slots, then snap on the clear ring base and cover; the step often missed is aligning the side vents so air can circulate around the thermostat.

What maintenance will the Honeywell sRSV-420 need after installation?

Periodically remove the clear cover and wipe dust from the side vents and interior so airflow reaches the thermostat; the tumbler lock may need a drop of light lubricant if the key stiffens over time.

What is the first limit that appears when the Honeywell sRSV-420 is used continuously in a high-traffic area?

The clear plastic cover can scratch or yellow from repeated handling and UV exposure, reducing visibility of the thermostat display inside.

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