Multi-Zone Thermostats
Choose smart thermostat replacements for each existing low-voltage HVAC zone, and avoid confusing room sensors or fans with true zone control.
PRO1 IAQ T855iSH 8" Backlit WiFi Thermostat: Large 8" Backlit Display
This WiFi thermostat gives you precise control over your home's comfort, perfect for homeowners who want to manage energy use without sacrificing convenience. The large 8-inch backlit display and glow-in-the-dark button make it easy to read and adjust, even in a dark hallway at night.
Instead of just programming a schedule, use the auto changeover to let the thermostat switch between heating and cooling as needed. You can set temperature limits and enable keypad lockout to prevent tampering, which is great for rental properties or homes with curious kids. The filter alert reminds you to replace the filter, helping your HVAC system run efficiently.
Compatible with 2H/2C conventional and 5H/3C heat pump systems, this thermostat handles most residential setups. Installation is straightforward with color-coded terminals and a universal sub-base, so you can replace your old thermostat in under an hour.
Manage your thermostat remotely via the app, and pair it with Amazon Alexa or Google Assistant for voice control. You can adjust the temperature from bed, check the forecast, or set a schedule without leaving the couch.
Features
- WiFi-Enabled with Programmable Options
- Advanced HVAC Compatibility
- Precision Control & Security Features
- Reliable & Easy Installation
- Large 8" Backlit Display
General specs
- Brand: PRO1 IAQ
- Model: T855iSH
- Seller: Retailer
- ID: B0DYL7VR8Z
- WiFi: Yes
- Mounting: Junction Box
- Backlight: Blue
- Control Fan: Yes
- Button Glow: Yes
- Keypad Lock: Yes
- Display Size: 8 inches
- Power Supply: 24V
- Programmable: 7-Day, Non-Programmable
- Alerts Filter: Yes
- Auto Changeover: Yes
- Limits Setpoint: Yes
- Compatibility Hvac: 2H/2C Conventional, 5H/3C Heat Pump
- Base Sub Universal: Yes
- Coded Color Terminals: Yes
- Calibration Room Temp: Yes
- First listed by seller: May 28, 2026
If you are interested in more details, you can find full information on the seller's page.
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| Price | €142.31 | €187.93 | €145.45 | €156.03 | €46.32 | €58.56 |
| Seller | Retailer | Retailer | Retailer | Retailer | Retailer | Retailer |
| Update | Jun 24, 2026 | Jun 24, 2026 | Jun 24, 2026 | Jun 24, 2026 | May 29, 2026 | Jun 24, 2026 |
PRO1 IAQ T855iSH Large 8" Backlit Display
€142.31
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