Honeywell DT90 manual

Honeywell DT90
  • Number of pages: 8
  • Filetype: PDF

EN0H 8578 UK07 R1 12/08



The new DT90 family of digital room thermostats is a range of market leading products designed to provide comfort with economy in modern heating systems. Its large display and simple button interface make DT90 extremely easy to use.
Energy efficiency is addressed by state-of-the-art TPI control performance and an ECO button energy saving feature.
Applications include control of gas or oil-fired boiler systems, underfloor heating, electric heating and zoning systems.
With a modern fresh look that complements any style of décor, and a range of valued features for users and installers alike, DT90 sets the standard for simple environmentally-friendly room thermostats.
Energy saving TPI control performance
Advanced self-learning control adapts to the
environment and ensures close temperature control with minimum energy usage
Slim modern styling
Large high contrast display with easy-to-read
Simple user interface
Temperature setting procedure eliminates the
risk of accidental setpoint change
Display shows room temperature, with option
to inquire about setpoint
5°C to 35°C setpoint range with 0.5°C
Temperature set using up or down buttons
Off/standby button, allowing manual switch off,
with frost protection active
Adjustable off/standby setpoint 5°C to 16°C or
DT90 can be set to off completely
Battery powered by 2 x AA (LR6) alkaline cells
Up to 4 years battery life (minimum 2 years),
with battery low warning
Simple battery change by unclipping front
Installer Mode allows the thermostat to be
customised for the application and the needs of the user
NVRAM storage of setup parameters, ensuring
these are never lost
Setpoint limits can be programmed in
24…230Vac SPDT potential-free contacts for
simple 2-wire installation
8 A resistive, 3 A inductive switch rating
Surface or switch-box mounting options
Sensor fault self-diagnostics
Heat/cool changeover operation mode possible
Energy saving ECO button allows user to
change to a lower, energy saving setpoint for a timed period of their choosing (1…24 hours)
Display shows countdown of time remaining in
ECO energy saving mode
Honeywell DT90

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Number of questions: 9

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Kieran, 30-11-2020 18:36:33 No comments

How can you racing thermostat to wireless box

How can you racing thermostat to wireless box
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Stuart, 6-1-2021 12:47:37 No comments

Setting tmer

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Michael Pursall, 12-10-2021 13:46:03 No comments


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dominic, 11-10-2021 12:57:22 No comments

when i try to bond the DT90e on the second step witch is to move down from inst to count, why will it not let me scroll down? i cn go up and then down but not down to count. Can you help

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Paul, 7-7-2021 13:24:21 No comments

how do I bind it to my heating system

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Geraldine Matthews, 13-5-2021 15:28:49 No comments

How do I replace the AAu batteries?

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Allan, 6-4-2021 21:23:50 No comments

What does it mean if neither red nor green light is showing on the wireless relay. If the thermostat is working correctly shouldn’t the relay be showing a constant green light?

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Malcolm, 16-2-2021 19:10:43 No comments

Hi, I have just purchased the DT 90 E stat to replace an old 3 wire stat, forgive me but which terminal should the third (load ) wire be connected to, at the moment I am blowing fuses or getting no reaction from the boiler as in no heat. I would appreciate any advice. Many thanks.

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Lesley Collins, 2-1-2021 09:36:10 No comments

Our thermostat is intermittently sulking and although it looks like it’s working the rads get cold. Have tried new batteries and turning it on and iff

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View the manual for the Honeywell DT90 here, for free. This manual comes under the category Thermostat and has been rated by 5 people with an average of a 9. This manual is available in the following languages: English. Do you have a question about the Honeywell DT90 or do you need help? Ask your question here

Honeywell DT90 specifications

Brand Honeywell
Model DT90
Product Thermostats
EAN 5025121386128
Language English
Filetype PDF
Operational conditions
Accuracy 0.5 °C
Temperature range (T-T) 5 - 35 °C
Memory function
Product colour White
Display LCD
Number of batteries supported 2
Battery voltage 230 V
Battery life 2 year(s)
Packaging content
Batteries included
Remote control included
Weight & dimensions
Width 90 mm
Depth 27 mm
Height 92 mm
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Frequently Asked Questions

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