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PRO1 IAQ T855 Low Voltage Thermostat - Standard Thermostats
PRO1 IAQStandard Thermostats

PRO1 IAQ T855 Low Voltage Thermostat

The PRO1 IAQ T855 is a square, push-button low voltage thermostat for heat and cool applications. It supports 2H/2C conventional and 3H/2C heat pump staging with automatic changeover and 7-day programming. The…

SKU 3G-OTH-71052

Also listed as: T 855 · T-855

Brand
PRO1 IAQ
Item
T855 Low Voltage Thermostat
Category
Standard Thermostats
Available to Order
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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

PRO1 IAQ
Manufacturer Part Number
T855
Type
Auto, B/C/G/O/RC/RH/W2/W/E/Terminal Designations/Y2
Shape
Square
Stages
2H/2C Conventional, 3H/2C Heat Pump
Application
Heat and Cool
Control Type
Push Button
Changeover Type
Automatic
Mounting Direction
Horizontal
Terminal Designations
Y2
Humidification Control
No
Programming Capability
7 Day
Temperature Control Range
44° to 90°F

Technical Documents

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PRO1 IAQ Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The PRO1 IAQ T855 is a square, push-button low voltage thermostat for heat and cool applications. It supports 2H/2C conventional and 3H/2C heat pump staging with automatic changeover and 7-day programming. The thermostat has a temperature control range of 44° to 90°F and includes terminal designations Y2, B/C/G/O/RC/RH/W2/W/E.

Frequently Asked Questions

What is the PRO1 IAQ T855 thermostat used for?

The PRO1 IAQ T855 is a low voltage thermostat for residential or light commercial heat and cool systems. It supports 2H/2C conventional and 3H/2C heat pump staging with automatic changeover, making it suitable for multi-stage HVAC control in homes and offices.

What are the specifications of the PRO1 IAQ T855 thermostat?

The PRO1 IAQ T855 is a square, push-button thermostat with a temperature control range of 44° to 90°F. It offers 7-day programming, automatic changeover, and terminal designations Y2, B/C/G/O/RC/RH/W2/W/E. It supports 2H/2C conventional and 3H/2C heat pump staging.

Where to buy the PRO1 IAQ T855 thermostat worldwide?

3G Electric supplies the PRO1 IAQ T855 thermostat 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 on this model.

How to install the PRO1 IAQ T855 thermostat?

Install the PRO1 IAQ T855 by mounting it horizontally on a wall, connecting low voltage wires to terminals Y2, B/C/G/O/RC/RH/W2/W/E as per system type. Ensure power is off during wiring. Follow the manual for 7-day programming and automatic changeover setup.

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 standard thermostats. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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