Vaillant
Vaillant Automatic Bypass Valve 150238
Automatic bypass valve, part 150238, for Vaillant Ecomax, VU and VUW gas boilers.
At a glance
- Appliance family: Ecomax, VU and VUW gas boilers
- Also known as AUTOMATIC-BYPASS-VALVE, 1373906
£46.55
£38.79 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 automatic bypass valve, part number 150238, is a hydraulic component fitted to Vaillant Ecomax, VU and VUW gas boilers. It maintains a minimum flow rate through the primary circuit when system demand falls, protecting the heat exchanger and pump from excessive temperature rise or restricted flow. It is a serviceable part intended for replacement when the valve no longer regulates flow correctly.
Signs this part needs replacing
- Boiler locks out or overheats when heating demand is low, such as when zone valves close
- Pump noise or kettling from the primary circuit during reduced flow conditions
- Uneven or reduced heat output across the system despite the pump running
- Visible leakage, weeping or corrosion around the bypass valve body
- The valve no longer adjusts or holds its setting when turned
Before you order
- Confirm the boiler model and variant against the fitment list above
- Check the existing valve for the part number 150238 or an equivalent marking
- Verify the fault is with the bypass valve and not the pump, diverter valve or system controls
- Isolate and drain the appliance before removal, and follow the manufacturer's instructions for refilling and recommissioning
Compliance
| GC number | E24-176 |
|---|---|
| Barcode / EAN | 4024074335130 |
| Alternative numbers | AUTOMATIC-BYPASS-VALVE, 1373906 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT ECOmax 613 VU 126 E-C (2000-2001) | 41-044-20 | 41-044-20 | — | — |
| VAILLANT ECOmax 618 VU 196 E-C (2000-2001) | 41-044-21 | 41-044-21 | — | — |
| VAILLANT ECOmax 622 VU 246 E-C (2000-2001) | 41-044-22 | 41-044-22 | — | — |
| VAILLANT ECOmax 824 VUW 246 E-C (1999-2001) | 47-044-07 | 47-044-07 | — | — |
| VAILLANT ECOmax 828 VUW 286 E-C (1999-2001) | 47-044-08 | 47-044-08 | — | — |
| VAILLANT VU 126 E-C | 41-044-20 | 41-044-20 | — | — |
| VAILLANT VU 126/2-C | 41-044-27 | 41-044-27 | — | — |
| VAILLANT VU 186/2-C | 41-044-28 | 41-044-28 | — | — |
| VAILLANT VU 196 E-C | 41-044-21 | 41-044-21 | — | — |
| VAILLANT VU 226/2-C | 41-044-29 | 41-044-29 | — | — |
Showing 10 of 26 compatible appliances.
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 — ECOmax 824 VUW 246 E-C (1999-2001) (GC 47-044-07), ECOmax 828 VUW 286 E-C (1999-2001) (GC 47-044-08), VUW 246 E-C (GC 47-044-07), VUW 286 E-C (GC 47-044-08)
manualmanualVAILLANT appliance manual — VU 126/2-C (GC 41-044-27), VU 186/2-C (GC 41-044-28), VU 226/2-C (GC 41-044-29), VU 356-C (GC 41-044-43), VU 356/2-C (GC 41-044-43), VUW 246/2-C (GC 47-044-12), VUW 286/2-C (GC 47-044-17), VUW 356-C (GC 47-044-27), ecoMAX 613/2E VU 126/2 C (2001-2006) (GC 41-044-27), ecoMAX 618/2E VU 186/2 C (2001-2006) (GC 41-044-28), ecoMAX 622/2E VU 226/2 C (2001-2006) (GC 41-044-29), ecoMAX 635 E VU 356-C (2004-2006) (GC 41-044-43), ecoMAX 635 VU 356/2-C (2006-2008) (GC 41-044-43), ecoMAX 824/2 E-C VUW 246/2 E-C (2001-2006) (GC 47-044-12), ecoMAX 828/2E VUW 286/2 C (2001-2006) (GC 47-044-17), ecoMAX 835E VUW 356 C (2002-2006) (GC 47-044-27)
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