Vaillant
Vaillant Sensor 0020209505
Vaillant thermistor sensor 0020209505 for Ecotec Exclusive VU and VUW gas boilers.
At a glance
- Appliance family: Ecotec Exclusive VU and VUW
- Also known as 1387988
£175.31
£146.09 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 Vaillant 0020209505 is a sensor (thermistor) used in Vaillant Ecotec Exclusive gas boilers. It forms part of the appliance's temperature sensing circuit, feeding temperature information back to the boiler's control board so that heating and hot water operation can be regulated. It is listed for the Ecotec Exclusive VU and VUW range.
Signs this part needs replacing
- Boiler locks out or shuts down shortly after firing, with a temperature-related fault indicated
- Flow or return temperature readings that are erratic or clearly inconsistent with the system
- Domestic hot water temperature that fluctuates or fails to reach the set point
- Short cycling, where the boiler fires and stops repeatedly over short intervals
- Heating or hot water performance that degrades progressively as the sensor output drifts
Before you order
- Confirm the boiler model and GC number against the fitment list before ordering
- Check the appliance's fault history to establish whether the sensor is the cause rather than the control board or wiring
- Inspect the sensor lead and plug connections for damage or corrosion before replacing the part
- Confirm the sensor position on the appliance, as more than one sensor may be fitted
Compliance
| Alternative numbers | 1387988 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT VU 256/5-7 | 41-694-02 | 41-694-02 | — | — |
| VAILLANT VUW 356/5-7 | 47-044-66 | 47-044-66 | — | — |
| VAILLANT VUW 436/5-7 | 47-044-67 | 47-044-67 | — | — |
| VAILLANT ecoTEC EXCLUSIVE 627 VU 256/5-7 (2016) | 41-694-02 | 41-694-02 | — | — |
| VAILLANT ecoTEC EXCLUSIVE 835 VUW 356/5-7 (2016) | 47-044-66 | 47-044-66 | — | — |
| VAILLANT ecoTEC EXCLUSIVE 843 VUW 436/5-7 (2016) | 47-044-67 | 47-044-67 | — | — |
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.
VAILLANT appliance manual — VU 256/5-7 (GC 41-694-02), ecoTEC EXCLUSIVE 627 VU 256/5-7 (2016) (GC 41-694-02)
manualmanualVAILLANT appliance manual — VUW 356/5-7 (GC 47-044-66), VUW 436/5-7 (GC 47-044-67), ecoTEC EXCLUSIVE 835 VUW 356/5-7 (2016) (GC 47-044-66), ecoTEC EXCLUSIVE 843 VUW 436/5-7 (2016) (GC 47-044-67)
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