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Honeywell T3 Programmable Thermostat  

Honeywell -T3 -Programmable -Thermostat- PRO

Thermostat Interface

Screen and Button Overview

Status Icons

Navigation Icons

Menu & Navigation Icons

Navigating the Menu

Menu

Heating Schedule
Your Thermostat comes with the following default schedule. Follow the next steps to adjust heating schedule.Honeywell -T3 -Programmable -Thermostat- 14

Adjusting the Schedule

Copy Schedule

Delete Period

Settings (Date & Time)

Device Modes

Automatic Operation
During normal use your Thermostat will follow the programmed schedule – indicated by theHoneywell -T3 -Programmable -Thermostat- 45 iconHoneywell -T3 -Programmable -Thermostat- 37

Temporary override
Press the + or- set the new desired temperature. The programmed schedule will resume at the next programmed setpoint.

Honeywell -T3 -Programmable -Thermostat- 38

+1hr Timed override
PressHoneywell -T3 -Programmable -Thermostat- 13 for a 1 hour timed override. PressHoneywell -T3 -Programmable -Thermostat- 13 again to cancel

Honeywell -T3 -Programmable -Thermostat- 39

Manual Operation

The set temperature is followed permanently – indicated by theHoneywell -T3 -Programmable -Thermostat- 41 icon.Honeywell -T3 -Programmable -Thermostat- 37

Permanent override

Press the +or- buttons to adjust the set temperature. This temperature is set until manually changed again.Honeywell -T3 -Programmable -Thermostat- 39

Honeywell -T3 -Programmable -Thermostat- 12Standby mode (with frost protect)
Save energy by switching the heating off when not required – e.g. during warmer summer months, or when doors and windows are open for extended periods of time. If the temperature drops to 5°C the heating will come on to prevent the heating pipes freezing.

Honeywell -T3 -Programmable -Thermostat- 44

Keypad Lock

OptimizationHoneywell -T3 -Programmable -Thermostat- 49

Honeywell -T3 -Programmable -Thermostat- 50Optimization
Your Thermostat has optimization functions that aim to save energy while maintaining suitable comfort levels. The Thermostat displays during the optimization period if set. By default optimization is disabled, see instructions on the installation guide on how to activate it.

Changing the Batteries (T3 & T3R only)

Table Stand a 7 nd Wall Mount (T3R only)

Table StandHoneywell -T3 -Programmable -Thermostat- 54

Wall Mount

Honeywell -T3 -Programmable -Thermostat- 55

Wireless Receiver Box (T3R only)
The T3R Thermostat communicates wirelessly to the Receiver Box which is wired to the boiler. If the Thermostat loses wireless communication or becomes faulty, the boiler can be switched on or off manually using the button on the Receiver Box.

To manually override the boiler using the Receiver Box:

Troubleshooting

All models
Screen is blank Replace the batteries (T3 & T3R only).

Check the OpenTherm boiler has power (T3M only). Contact installer.

Thermostat showsHoneywell -T3 -Programmable -Thermostat- 52 Batteries have less than 10% power and need to be replaced soon.
Thermostat shows Honeywell -T3 -Programmable -Thermostat- 53 +Honeywell -T3 -Programmable -Thermostat- 52 Batteries are critically low and need to be replaced immediately – see ‘Changing the Batteries’.
Thermostat shows  but the boiler does not switch on. The boiler cycles on and off as it controls the temperature, and sometimes the  icon will be displayed when the boiler has cycled off.

If the boiler doesn’t switch on after a long period of time contact your installer.

Heating system does not respond to temperature adjust- ments. Make sure the set temperature is higher than the actual room temperature.

Check the heating system is powered on.

Check the Receiver Box is powered and the Thermostat has a wireless signal (T3R only).

Thermostat showsHoneywell -T3 -Programmable -Thermostat- 53  + – – The temperature sensor of your Thermostat is faulty, contact your installer to repair or replace the Thermostat.
Honeywell -T3 -Programmable -Thermostat- 53+ SERV Boiler service reminder (UK Only). The boiler is due to be serviced. Please contact your landlord or local housing authority.
T3R (Wireless) Thermostat & Receiver Box only
Thermostat is flashing Honeywell -T3 -Programmable -Thermostat- 53 +Honeywell -T3 -Programmable -Thermostat- 56  and Receiver BoxHoneywell -T3 -Programmable -Thermostat- 56  LED is flashing RED. Wireless signal lost – Move the Thermostat to another location to try and restore communication.
Thermostat is flashing Honeywell -T3 -Programmable -Thermostat- 53+Honeywell -T3 -Programmable -Thermostat- 56  and Receiver BoxHoneywell -T3 -Programmable -Thermostat- 56  LED is off. Check Receiver Box has power by pressing the button to switch boiler on.

If Receiver Box has power then no wireless binding data stored – Follow binding procedure in the installation guide or contact your installer.

Receiver Box  LED is flashing ORANGE. Receiver Box is in binding mode – will time out of this mode after 3 minutes.
T3M (OpenTherm) Thermostat only
An OpenTherm boiler can report alerts back to the Thermostat which can be useful when contacting an installer or maintenance engineer. You can view these in the ‘OpenTherm® boiler alerts’ menu.
Description ID Error code OT Reading
Service request 001 01SR 0 = service not required 1 = service required
Low water pressure 002 02WP 0 = no WP fault 1 = WP fault
Gas/flame fault 003 03GF 0 = no GF fault 1 = GS fault
Air pressure fault 004 04AF 0 = no AP fault 1 = AP fault
Water Over Temperature 005 05WT 0 = no OVT fault 1 = OVT fault
OEM specific 006 06OS Boiler manufacturer specific code

Resideo

Reference

Download manual:

Honeywell T3 Programmable Thermostat USER MANUAL

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Honeywell T3 Programmable Thermostat USER MANUAL

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