Honeywell
Honeywell DT4R Wireless Room Thermostat YT42WRFT20
Honeywell DT4R wireless on/off room thermostat, part number YT42WRFT20, supplied in white.
At a glance
- Also known as 4200667
£74.94
£62.45 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Honeywell DT4R is a wireless on/off room thermostat supplied in white. It is used to control heating demand in a domestic heating system by switching the heat source on and off according to room temperature. The part number is YT42WRFT20.
Signs this part needs replacing
- The heating does not respond when the room temperature falls below the set point
- The thermostat display is blank, flickering or unresponsive
- Room temperature readings are consistently inaccurate
- The wireless signal to the receiver is lost or intermittent
- The heating stays on after the set point has been reached
Before you order
- Confirm the existing thermostat is a Honeywell DT4R, or that YT42WRFT20 is the correct part for your system
- Check that your system uses on/off control rather than a modulating or OpenTherm control
- Verify that the receiver and wiring already installed are compatible with this thermostat
- Check the model and part number on the existing unit before ordering
Compliance
| Alternative numbers | 4200667 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| SPECIAL OFFERS Honeywell Controls | — | — | — |
Documents & drawings
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
No technical questions yet for this part.
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