Honeywell DT90E User Manual

*
The purpose of this device is to control the temperature
of the HEATING when the timer allows it to be switched
on.
The hot water will not be affected in any way.
Normal operation of the thermostat
Normal Display
The display will normally show the room temperature
measured by the thermostat.
If the flame symbol is visible*, this means that the boiler
should be on.
To enquire about the set temperature
Simply press one of the arrow buttons and the display
will show the set temperature. After a few seconds it
will go back to showing the room temperature.
To change the set temperature
Keep pressing the arrow buttons and the display will
change to show the new set temperature.
Press the S button to increase the temperature, and
the ▼ button to decrease the temperature.
To switch on or off
Press and hold the button marked
for 2 seconds to switch off.
In the bottom right corner display will show this symbol.
To switch the thermostat back on, press and hold the
same button again for 2 seconds. The symbol in the
bottom right hand corner will disappear.
50029850-002
GUIDE TO THE USE OF THE DT90E ROOM THERMOSTAT
Honeywell
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Honeywell DT90E Specifications

General

Type	Digital Room Thermostat
Power Supply	2 x AA batteries
Temperature Range	5°C to 35°C
Display	LCD
Mounting	Wall-mounted
Control Mode	On/Off
Switching Voltage	230V AC
Frost Protection	Yes
Certification	CE
Switching Current	3A (resistive)
Accuracy	±0.5°C

Summary

Guide to Using the DT90E Room Thermostat

Normal Display and Operation

Shows room temperature and flame symbol indicating boiler status. Explains normal display.

Enquiring About Set Temperature

Press arrow buttons to view set temperature temporarily. Display reverts to room temperature.

Changing the Set Temperature

Press and hold arrow buttons to adjust set temperature. Use ▲ to increase, ▼ to decrease.

Switching the Thermostat On and Off

Press and hold the marked button for 2 seconds to switch off. Symbol indicates off state.

Energy Saving ECO Button Operation

Starting Energy Saving (ECO Mode)

Press the green ECO button to activate energy saving. Set desired hours for this mode.

Setting ECO Mode Duration

Use ▲ or ▼ buttons to set the duration for ECO mode, from 1 to 24 hours.

ECO Mode Display Information

Display shows 'ECO', remaining time, and room temperature. Alternates between views.

Exiting ECO Energy Saving Mode

Press the green ECO button again to deactivate ECO mode. Thermostat returns to normal control.