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Honeywell TR21-H/U Wall Mount Room Temperature Sensor - Room Temperature Sensors
HoneywellRoom Temperature Sensors

Honeywell TR21-H/U Wall Mount Room Temperature Sensor

The Honeywell TR21-H/U is a wall-mount room temperature sensor in a conduit-box housing with wireless transmission. It offers a temperature accuracy of ±1 °F (12 °C to 30 °C) and is compatible with building…

SKU 3G-OTH-69517

Also listed as: TR21HU · TR21 H U · TR21-H-U

Brand
Honeywell
Item
TR21-H/U Wall Mount Room Temperature Sensor
Part Number
TR21-H/U
Category
Room Temperature Sensors
Available to Order
Also known as:TR21-H/UHoneywell
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

Honeywell
Manufacturer Part Number
TR21-H/U
Display
No Display
Housing Type
Conduit Box
Product Type
Temperature Sensor
Mounting Location
Wall Mount
Temperature Signal
Wireless Transmission
Temperature Accuracy
±1 °F (12 °C to 30 °C)
Temperature Signal Output
Wireless Transmission
For Use With Building Automation Systems
Building Automation System Compatible

Technical Documents

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Honeywell Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Honeywell TR21-H/U is a wall-mount room temperature sensor in a conduit-box housing with wireless transmission. It offers a temperature accuracy of ±1 °F (12 °C to 30 °C) and is compatible with building automation systems.

Frequently Asked Questions

What is the Honeywell TR21-H/U temperature sensor used for?

The Honeywell TR21-H/U is a wall-mount room temperature sensor designed for building automation systems. It provides wireless temperature transmission to HVAC controllers, enabling energy-efficient climate monitoring in commercial facilities, offices, and industrial spaces.

What are the specifications of the Honeywell TR21-H/U?

The Honeywell TR21-H/U is a wall-mount temperature sensor with a conduit-box housing. It features wireless transmission output, a temperature accuracy of ±1 °F (12 °C to 30 °C), and is compatible with building automation systems. It has no display and carries MPN TR21-H/U.

Where to buy the Honeywell TR21-H/U worldwide?

You can source the Honeywell TR21-H/U through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time.

How to install the Honeywell TR21-H/U temperature sensor?

Mount the Honeywell TR21-H/U on a wall using the conduit-box housing. Ensure the sensor is away from direct heat sources and drafts. Pair it with your building automation system following the manufacturer's wireless pairing instructions. Verify temperature accuracy after installation.

Used in

Common applications for Honeywell
Commercial kitchen and inflight-catering steam boilers — RM7890 / RM7895 flame relays with UV detection
Food-processing ramp-and-dwell ovens — DBC2000E / DBC2100E controllers
Hotel and hospital boiler plants — VR8205 combination gas controls
Petrochemical tank-farm heating — V4xxx gas-valve bodies with ML7420 actuators
Retrofit swap-outs from legacy Fireye / Satronic — Honeywell replacement kits
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Honeywell Products

3G Electric supplies Honeywell room temperature sensors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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The Honeywell TR23/U is a wall-mount room temperature sensor housed in a conduit box, featuring an analog display. It transmits temperature signals wirelessly and is compatible with building automation systems. Temperature accuracy is ±1 °F (12 °C to 30 °C). Typical applications include HVAC control in commercial or industrial facilities
Honeywell
The Honeywell TR23/U is a wall-mount room temperature sensor housed in a conduit box, featuring an analog display. It transmits temperature signals wirelessly and is compatible with building automation systems. Temperature accuracy is ±1 °F (12 °C to 30 °C). Typical applications include HVAC control in commercial or industrial facilities

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