Baxi
Baxi Wiring Harness Sensors TR-04 7854146
Wiring harness for sensors (TR-04), part 7854146, for Baxi Aquaheat HD/HWI and HI/HWI appliances.
At a glance
- Appliance family: Aquaheat HD/HWI and HI/HWI
- Also known as 1129404
£58.40
£48.67 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 Baxi 7854146 is a wiring harness for sensors, identified by the TR-04 designation. It carries sensor signals within Baxi Aquaheat HD/HWI and HI/HWI appliances. The harness connects the sensor circuit to the appliance control, allowing temperature and status readings to be transmitted correctly.
Signs this part needs replacing
- Sensor readings that are erratic, intermittent or absent at the control
- Fault codes or lockouts linked to sensor signal loss
- Visible damage to the harness insulation, such as chafing, cracking or heat damage
- Corroded, loose or discoloured connector terminals on the harness
- Sensor faults that persist after the sensor itself has been checked
Before you order
- Confirm your appliance model against the fitment list above
- Check the existing harness for its part number and TR-04 marking
- Inspect the sensor connectors and control plug for damage before fitting
- Verify that the fault is in the wiring rather than the sensor or control board
Compliance
| Alternative numbers | 1129404 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| BAXI AQUAHEAT HD/HWI 12/50 | — | — | — | |
| BAXI AQUAHEAT HD/HWI 12/50 WITH HEAT METER & MERCURIUS | — | — | — | |
| BAXI AQUAHEAT HI/ HWI - 4/50 | — | — | — | |
| BAXI AQUAHEAT HI/HWI - 14/50 | — | — | — |
Documents & drawings
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No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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