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PRO1 IAQ Low Voltage Thermostat: Heat or Cool, Manual, B/C/E/G/O/R/W2/Terminal Designations - Digital Thermostats
PRO1 IAQDigital Thermostats

PRO1 IAQ Low Voltage Thermostat: Heat or Cool, Manual, B/C/E/G/O/R/W2/Terminal Designations

The PRO1 IAQ T621-2 is a square, push-button digital thermostat for heat-or-cool applications, operating on 18V AC with manual changeover and system settings for Cool, Emergency Heat, Heat, and Off. It features an…

SKU 3G-OTH-70492

Brand
PRO1 IAQ
Item
Low Voltage Thermostat: Heat or Cool, Manual, B/C/E/G/O/R/W2/Terminal Designations
Category
Digital Thermostats
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Technical Specifications

PRO1 IAQ
Manufacturer Part Number
T621-2
Type
Manual, B/C/E/G/O/R/W2/Terminal Designations, Auto-On
Shape
Square
Voltage
18V AC
Digit Size
Easy Read
Application
Heat or Cool
Control Type
Push Button
Fan Settings
Auto-On
Key Features
Easy Access Battery Compartment
Changeover Type
Manual
System Settings
Cool-Emergency Heat-Heat-Off
Mounting Direction
Horizontal
Terminal Designations
B
Temperature Differential
0.2°F to 2°F
Temperature Control Range
44° to 90°F
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PRO1 IAQ Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The PRO1 IAQ T621-2 is a square, push-button digital thermostat for heat-or-cool applications, operating on 18V AC with manual changeover and system settings for Cool, Emergency Heat, Heat, and Off. It features an easy-access battery compartment, Auto-On fan setting, a temperature control range of 44° to 90°F, and a selectable temperature differential of 0.2°F to 2°F. Terminal designations include B, and the thermostat mounts horizontally.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is the PRO1 IAQ T621-2 thermostat used for?

The PRO1 IAQ T621-2 is a digital thermostat for heat-or-cool applications in residential or light commercial HVAC systems. It provides manual changeover between Cool, Emergency Heat, Heat, and Off, with an Auto-On fan setting. It is suitable for 18V AC systems and includes an easy-access battery compartment.

What are the specifications of the PRO1 IAQ T621-2 thermostat?

The PRO1 IAQ T621-2 operates on 18V AC with a temperature control range of 44° to 90°F and a selectable temperature differential of 0.2°F to 2°F. It features push-button controls, a square shape, horizontal mounting, and terminal designations including B. System settings are Cool, Emergency Heat, Heat, and Off with manual changeover.

Where to buy the PRO1 IAQ T621-2 thermostat worldwide?

3G Electric supplies the PRO1 IAQ T621-2 thermostat to customers worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time; we source and deliver this thermostat to meet your project needs.

How to install the PRO1 IAQ T621-2 thermostat?

To install the PRO1 IAQ T621-2, mount the thermostat horizontally on a wall, connect the 18V AC power and B terminal wiring per system requirements, and set the temperature differential (0.2°F to 2°F) and system settings (Cool, Emergency Heat, Heat, Off). Always follow local electrical codes and the manufacturer's instructions for safe installation.

Used in

Common applications for PRO1 IAQ
Commercial HVAC maintenance — PRO1 IAQ T855SH thermostat for multi-stage heat pump control in office buildings
Facility energy management — PRO1 IAQ T805 programmable thermostat for 7-day scheduling in retail spaces
Light commercial retrofit — PRO1 IAQ T501M analog thermostat for simple heat/cool control in small shops
Indoor air quality monitoring — PRO1 IAQ R751WO wireless sensor for temperature and motion detection in conference rooms
Heat pump system replacement — PRO1 IAQ T625-2 thermostat for 2H/1C heat pump staging in residential units
Thermostat guard replacement — PRO1 IAQ T150K replacement keys for securing T150 plastic guards in public areas

PRO1 IAQ Products

3G Electric supplies PRO1 IAQ digital thermostats. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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