Vaillant
Vaillant Bypass Valve Assembly 178980
Vaillant bypass valve assembly 178980 for ecoTEC Plus VU and VUW boilers, controlling flow in the boiler hydraulic circuit.
At a glance
- Appliance family: ecoTEC Plus VU and ecoTEC Plus VUW.
- Also known as 1376538
Showing prices
£36.22
£30.18 ex. VAT · VAT at 20%
Available to order · 3 working days
Available to order · 3 working days
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Vaillant 178980 is a bypass valve assembly for Vaillant ecoTEC Plus VU and VUW boilers. It sits in the boiler's isolation and hydraulic circuit and controls flow between the heating circuit and the appliance. The valve helps maintain correct circulation through the boiler, including on the ecoTEC PLUS 612 VU 126/5-5 (41-044-60).
Signs this part needs replacing
- Boiler overheating or locking out during heating or hot water demand.
- Noisy operation from the boiler, such as kettling or whistling, when the bypass circuit is not regulating flow.
- Poor circulation or uneven heating across radiators.
- Frequent pressure fluctuations in the heating system.
- Boiler short-cycling or failing to maintain stable flow temperature.
Before you order
- Confirm the boiler model and GC number against the fitment list.
- Check the existing bypass valve part number or assembly marking where accessible.
- Verify the appliance is a Vaillant ecoTEC Plus VU or VUW variant.
- Check whether the boiler is a Guernsey/Jersey-only model variant if listed.
Compliance
| Barcode / EAN | 4024074477618 |
|---|---|
| Alternative numbers | 1376538 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT HOME COMBI 25 -A | 47-044-62 | 47-044-62 | — | — |
| VAILLANT HOME COMBI 30 -A | 47-044-63 | 47-044-63 | — | — |
| VAILLANT HOME COMBI 35 -A | 47-044-64 | 47-044-64 | — | — |
| VAILLANT HOME SYSTEM 12 -A | 41-044-94 | 41-044-94 | — | — |
| VAILLANT HOME SYSTEM 15 -A | 41-044-95 | 41-044-95 | — | — |
| VAILLANT HOME SYSTEM 18 -A | 41-044-96 | 41-044-96 | — | — |
| VAILLANT HOME SYSTEM 25 -A | 41-044-97 | 41-044-97 | — | — |
| VAILLANT VAILLANT ECOTEC EXCLUSIVE 832 - VUW 326/4 | — | — | — | |
| VAILLANT VAILLANT ECOTEC EXCLUSIVE 838 - VUW 386/4 | — | — | — | |
| VAILLANT VAILLANT ECOTEC PLUS 612 VU 126-3-5 | — | — | — |
Showing 10 of 378 compatible appliances.
Fitment listings are a guide, not a guarantee. Plant-room assemblies get modified on site more often than not. Send us the GC number off the data badge and a photo of the existing valve and we will confirm before anything is dispatched.
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.
manual
VAILLANT appliance manual — HOME COMBI 25 -A (GC 47-044-62), HOME COMBI 30 -A (GC 47-044-63), HOME COMBI 35 -A (GC 47-044-64)
manualmanualVAILLANT appliance manual — HOME SYSTEM 12 -A (GC 41-044-94), HOME SYSTEM 15 -A (GC 41-044-95), HOME SYSTEM 18 -A (GC 41-044-96), HOME SYSTEM 25 -A (GC 41-044-97)
manualmanualVAILLANT appliance manual — VU 126/3-5 (GC 41-044-44), VU 126/3-5 R1 (GC 41-044-44), VU 156/3-5 (GC 41-044-45), VU 156/3-5 R1 (GC 41-044-45), VU 186/3-5 (GC 41-044-46), VU 186/3-5 R1 (GC 41-044-46), VU 246/3-5 (GC 41-044-47), VU 246/3-5 R1 (GC 41-044-47), VU 306/3-5 (GC 41-044-48), VU 306/3-5 R1 (GC 41-044-48), VU 376/3-5 R1 (GC 41-044-49), VUW 246/3-3 R1 (GC 47-044-36), VUW 246/3-3 R2 (GC 47-044-36), VUW 246/3-5 (GC 47-044-31), VUW 246/3-5 R1 (GC 47-044-31), VUW 246/3-5 R3 (GC 47-044-31), VUW 286/3-3 (GC 47-044-30), VUW 286/3-3 R1 (GC 47-044-30), VUW 286/3-3 R2 (GC 47-044-30), VUW 316/3-5 (GC 47-044-32), VUW 316/3-5 R1 (GC 47-044-32), VUW 316/3-5 R3 (GC 47-044-32), VUW 316/3-5 R5 (GC 47-044-32), VUW 376/3-5 (GC 47-044-33), VUW 376/3-5 R1 (GC 47-044-33), ecoTEC PLUS 612 VU 126/3-5 (2005-2005) (GC 41-044-44), ecoTEC PLUS 612 VU 126/3-5 R1 (2005-2006) (GC 41-044-44), ecoTEC PLUS 615 VU 156/3-5 (2005-2005) (GC 41-044-45), ecoTEC PLUS 615 VU 156/3-5 R1 (2005-2006) (GC 41-044-45), ecoTEC PLUS 618 VU 186/3-5 (2005-2005) (GC 41-044-46), ecoTEC PLUS 618 VU 186/3-5 R1 (2005-2006) (GC 41-044-46), ecoTEC PLUS 624 VU 246/3-5 (2005-2006) (GC 41-044-47), ecoTEC PLUS 624 VU 246/3-5 R1 (2005-2006) (GC 41-044-47), ecoTEC PLUS 630 VU 306/3-5 (2005-2005) (GC 41-044-48), ecoTEC PLUS 630 VU 306/3-5 R1 (2005-2006) (GC 41-044-48), ecoTEC PLUS 637 VU 376/3-5 R1 - 2006-2006 (GC 41-044-49), ecoTEC PLUS 824 VUW 246/3-5 (2005-2005) (GC 47-044-31), ecoTEC PLUS 824 VUW 246/3-5 R1 (2005-2006) (GC 47-044-31), ecoTEC PLUS 824 VUW 246/3-5 R3 (2011-2012) (GC 47-044-31), ecoTEC PLUS 831 VUW 316/3-5 (2005-2005) (GC 47-044-32), ecoTEC PLUS 831 VUW 316/3-5 R1 (2005-2006) (GC 47-044-32), ecoTEC PLUS 831 VUW 316/3-5 R3 (2011-2012) (GC 47-044-32), ecoTEC PLUS 831 VUW 316/3-5 R5 (2013 - 2013) (GC 47-044-32), ecoTEC PLUS 837 VUW 376/3-5 (2005-2005) (GC 47-044-33), ecoTEC PLUS 837 VUW 376/3-5 R1 (2005-2006) (GC 47-044-33), ecoTEC PRO 24 VUW 246/3-3 R1 (2005-2006) (GC 47-044-36), ecoTEC PRO 24 VUW 246/3-3 R2 (2008-2012) (GC 47-044-36), ecoTEC PRO 28 VUW 286/3-3 (2005-2006) (GC 47-044-30), ecoTEC PRO 28 VUW 286/3-3 R1 (2005-2006) (GC 47-044-30), ecoTEC PRO 28 VUW 286/3-3 R2 (GC 47-044-30)
manualmanualVAILLANT appliance manual — VU 126/5-5 (GC 41-044-60), VU 126/5-5 R1 (GC 41-044-60), VU 126/5-5 R2 (GC 41-044-60), VU 126/5-5 R4 (GC 41-044-60), VU 156/5-5 (GC 41-044-61), VU 156/5-5 R1 (GC 41-044-61), VU 156/5-5 R2 (GC 41-044-61), VU 156/5-5 R4 (GC 41-044-61), VU 186/5-5 (GC 41-044-62), VU 186/5-5 R1 (GC 41-044-62), VU 186/5-5 R2 (GC 41-044-62), VU 186/5-5 R4 (GC 41-044-62), VU 246/5-5 (GC 41-044-63), VU 246/5-5 R1 (GC 41-044-63), VU 246/5-5 R2 (GC 41-044-63), VU 246/5-5 R4 (GC 41-044-63), VU 306/5-5 (GC 41-044-63), VU 306/5-5 R1 (GC 41-044-64), VU 306/5-5 R2 (GC 41-044-64), VU 306/5-5 R4 (GC 41-044-64), VU 376/5-5 (GC 41-044-65), VU 376/5-5 R1 (GC 41-044-65), VU 376/5-5 R2 (GC 41-044-65), VU 376/5-5 R4 (GC 41-044-65), VUW 246/5-5 (GC 47-044-40), VUW 246/5-5 R1 (GC 47-044-40), VUW 246/5-5 R2 (GC 41-044-63), VUW 246/5-5 R4 (GC 47-044-40), VUW 316/5-5 (GC 47-044-41), VUW 316/5-5 R1 (GC 47-044-41), VUW 316/5-5 R2 (GC 47-044-41), VUW 316/5-5 R4 (GC 47-044-41), VUW 376/5-5 (GC 47-044-42), VUW 376/5-5 R1 (GC 47-044-42), VUW 376/5-5 R2 (GC 47-044-42), VUW 376/5-5 R4 (GC 47-044-42), ecoTEC PLUS 612 VU 126/5-5 (2012-2012) (GC 41-044-60), ecoTEC PLUS 612 VU 126/5-5 R1 (2012-2013) (GC 41-044-60), ecoTEC PLUS 612 VU 126/5-5 R2 (2013-2015) (GC 41-044-60), ecoTEC PLUS 612 VU 126/5-5 R4 (2015-2015) (GC 41-044-60), ecoTEC PLUS 615 VU 156/5-5 (2012-2012) (GC 41-044-61), ecoTEC PLUS 615 VU 156/5-5 R1 (2012-2013) (GC 41-044-61), ecoTEC PLUS 615 VU 156/5-5 R2 (2013-2015) (GC 41-044-61), ecoTEC PLUS 615 VU 156/5-5 R4 (2015-2015) (GC 41-044-61), ecoTEC PLUS 618 VU 186/5-5 (2012-2012) (GC 41-044-62), ecoTEC PLUS 618 VU 186/5-5 R1 (2012-2013) (GC 41-044-62), ecoTEC PLUS 618 VU 186/5-5 R2 (2013-2015) (GC 41-044-62), ecoTEC PLUS 618 VU 186/5-5 R4 (2015-2015) (GC 41-044-62), ecoTEC PLUS 624 VU 246/5-5 (2012-2012) (GC 41-044-63), ecoTEC PLUS 624 VU 246/5-5 R1 (2012-2013) (GC 41-044-63), ecoTEC PLUS 624 VU 246/5-5 R2 (2013-2015) (GC 41-044-63), ecoTEC PLUS 624 VU 246/5-5 R4 (2015-2015) (GC 41-044-63), ecoTEC PLUS 630 VU 306/5-5 (2012-2012) (GC 41-044-63), ecoTEC PLUS 630 VU 306/5-5 R1 (2012-2013) (GC 41-044-64), ecoTEC PLUS 630 VU 306/5-5 R2 (2013-2014) (GC 41-044-64), ecoTEC PLUS 630 VU 306/5-5 R4 (2015-2015) (GC 41-044-64), ecoTEC PLUS 637 VU 376/5-5 (2012-2012) (GC 41-044-65), ecoTEC PLUS 637 VU 376/5-5 R1 (2012-2013) (GC 41-044-65), ecoTEC PLUS 637 VU 376/5-5 R2 (2013-2014) (GC 41-044-65), ecoTEC PLUS 637 VU 376/5-5 R4 (2014-2015) (GC 41-044-65), ecoTEC PLUS 824 VUW 246/5-5 (2012-2012) (GC 47-044-40), ecoTEC PLUS 824 VUW 246/5-5 R1 (2012-2013) (GC 47-044-40), ecoTEC PLUS 824 VUW 246/5-5 R2 (2013-2015) (GC 41-044-63), ecoTEC PLUS 824 VUW 246/5-5 R4 (2015-2015) (GC 47-044-40), ecoTEC PLUS 831 VUW 316/5-5 (2012-2012) (GC 47-044-41), ecoTEC PLUS 831 VUW 316/5-5 R1 (2012-2013) (GC 47-044-41), ecoTEC PLUS 831 VUW 316/5-5 R2 (2013-2015) (GC 47-044-41), ecoTEC PLUS 831 VUW 316/5-5 R4 (2015-2015) (GC 47-044-41), ecoTEC PLUS 837 VUW 376/5-5 (2012-2012) (GC 47-044-42), ecoTEC PLUS 837 VUW 376/5-5 R1 (2012-2013) (GC 47-044-42), ecoTEC PLUS 837 VUW 376/5-5 R2 (2013-2014) (GC 47-044-42), ecoTEC PLUS 837 VUW 376/5-5 R4 (2015-2015) (GC 47-044-42)
manualmanualVAILLANT appliance manual — VU 126/5-5 A R4 (GC 41-044-78), VU 156/5-5 A R4 (GC 41-044-79), VU 186/5-5 A R4 (GC 41-044-80), VU 246/5-5 A R4 (GC 41-044-82), VU 306/5-5 A R4 (GC 41-044-83), VU 376/5-5 A R4 (GC 41-044-85), VUW 256/5-5 R4 (GC 47-044-57), VUW 326/5-5 R4 (GC 47-044-58), VUW 356/5-5 R4 (GC 47-044-53), VUW 386/5-5 R4 (GC 47-044-60), ecoTEC PLUS 612 VU 126/5-5 A R4 (2015) (GC 41-044-78), ecoTEC PLUS 615 VU 156/5-5 A R4 (2015) (GC 41-044-79), ecoTEC PLUS 618 VU 186/5-5 A R4 (2015) (GC 41-044-80), ecoTEC PLUS 624 VU 246/5-5 A R4 (2015) (GC 41-044-82), ecoTEC PLUS 630 VU 306/5-5 A R4 (2015) (GC 41-044-83), ecoTEC PLUS 637 VU 376/5-5 A R4 (2015) (GC 41-044-85), ecoTEC PLUS 825 VUW 256/5-5 R4 (2015) (GC 47-044-57), ecoTEC PLUS 832 VUW 326/5-5 R4 (2015) (GC 47-044-58), ecoTEC PLUS 835 VUW 356/5-5 R4 (2015) (GC 47-044-53), ecoTEC PLUS 838 VUW 386/5-5 R4 (2015) (GC 47-044-60)
manualmanualVAILLANT appliance manual — VU 126/5-5 R6 (GC 41-694-20), VU 156/5-5 R6 (GC 41-694-21), VU 186/5-5 R6 (GC 41-694-22), VU 186/5-5 R6 LPG (GC 41-694-23), VU 246/5-5 R6 (GC 41-694-24), VU 306/5-5 R6 (GC 41-694-25), VU 306/5-5 R6 LPG (GC 41-694-26), VU 386/5-5 R6 (GC 41-694-27), VUW 196/5-5 R6 (GC 47-044-83), VUW 246/5-5 R6 (GC 47-044-84), VUW 246/5-5 R6 LPG (GC 47-044-85), VUW 286/5-5 R6 (GC 47-044-86), VUW 306/5-5 R6 (GC 47-044-82), ecoTEC PLUS 612 VU 126/5-5 R6 (2017) (GC 41-694-20), ecoTEC PLUS 615 VU 156/5-5 R6 (2017) (GC 41-694-21), ecoTEC PLUS 618 VU 186/5-5 R6 (2017) (GC 41-694-22), ecoTEC PLUS 618 VU 186/5-5 R6 LPG (2017) (GC 41-694-23), ecoTEC PLUS 624 VU 246/5-5 R6 (2017) (GC 41-694-24), ecoTEC PLUS 630 VU 306/5-5 R6 (2017) (GC 41-694-25), ecoTEC PLUS 630 VU 306/5-5 R6 LPG (2017) (GC 41-694-26), ecoTEC PLUS 637 VU 386/5-5 R6 (2017) (GC 41-694-27), ecoTEC PLUS 825 VUW 196/5-5 R6 (2017) (GC 47-044-83), ecoTEC PLUS 832 VUW 246/5-5 R6 (2017) (GC 47-044-84), ecoTEC PLUS 832 VUW 246/5-5 R6 LPG (2017) (GC 47-044-85), ecoTEC PLUS 835 VUW 306/5-5 R6 (2017) (GC 47-044-82), ecoTEC PLUS 838 VUW 286/5-5 R6 (2017) (GC 47-044-86)
manualmanualVAILLANT 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 — VUI 376/3-5 (GC 47-044-39), ecoTEC 937 VUI 376/3-5 (2006-2012) (GC 47-044-39)
manualmanualVAILLANT appliance manual — VUW 246/5-3 (GC 47-044-44), VUW 246/5-3 R1 (GC 47-044-44), VUW 246/5-3 R2 (GC 47-044-44), VUW 246/5-3 R4 (GC 47-044-44), VUW 286/5-3 (GC 47-044-45), VUW 286/5-3 R1 (GC 47-044-45), VUW 286/5-3 R2 (GC 47-044-45), VUW 286/5-3 R4 (GC 47-044-45), ecoTEC PRO 24 VUW 246/5-3 (2012-2012) (GC 47-044-44), ecoTEC PRO 24 VUW 246/5-3 R1 (2012-2013) (GC 47-044-44), ecoTEC PRO 24 VUW 246/5-3 R2 (2013-2015) (GC 47-044-44), ecoTEC PRO 24 VUW 246/5-3 R4 (2015-2015) (GC 47-044-44), ecoTEC PRO 28 VUW 286/5-3 (2012-2012) (GC 47-044-45), ecoTEC PRO 28 VUW 286/5-3 R1 (2012-2013) (GC 47-044-45), ecoTEC PRO 28 VUW 286/5-3 R2 (2013-2015) (GC 47-044-45), ecoTEC PRO 28 VUW 286/5-3 R4 (2015-2015) (GC 47-044-45)
manualmanualVAILLANT appliance manual — VUW 246/5-3 A R4 (GC 47-044-54), VUW 286/5-3 A R4 (GC 47-044-55), VUW 306/5-3 R4 (GC 47-044-52), ecoTEC PRO 24 VUW 246/5-3 A R4 (2015-2017) (GC 47-044-54), ecoTEC PRO 28 VUW 286/5-3 A R4 (2015-2017) (GC 47-044-55), ecoTEC PRO 30 VUW 306/5-3 R4 (2015) (GC 47-044-52)
manualmanualVAILLANT appliance manual — VUW 246/5-3 R6 (GC 47-044-88), VUW 286/5-3 R6 (GC 47-044-89), VUW 286/5-3 R6 LPG (GC 47-044-90), ecoTEC PRO 24 VUW 246/5-3 R6 (2017) (GC 47-044-88), ecoTEC PRO 28 VUW 286/5-3 R6 (2017) (GC 47-044-89), ecoTEC PRO 28 VUW 286/5-3 R6 LPG (2017) (GC 47-044-90)
manualmanualVAILLANT appliance manual — VUW 246/7-2 (GC 47-044-79), VUW 286/7-2 (GC 47-044-80), VUW 346/7-2 (GC 47-044-81), ecoTEC SUSTAIN 24 VUW 246/7-2 (2017) (GC 47-044-79), ecoTEC SUSTAIN 28 VUW 286/7-2 (2017) (GC 47-044-80), ecoTEC SUSTAIN 34 VUW 346/7-2 (2017) (GC 47-044-81)
manualmanualVAILLANT appliance manual — VUW 326/4-7 (GC 47-044-37), VUW 386/4-7 (GC 47-044-38), ecoTEC EXCLUSIVE 832 VUW 326/4-7 (GC 47-044-37), ecoTEC EXCLUSIVE 838 VUW 386/4-7 (GC 47-044-38)
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)
manualmanualVAILLANT appliance manual — ecoFIT PURE 612 - VU 126/6-3 (2016) (GC 41-694-03), ecoFIT PURE 615 - VU 156/6-3 (2016) (GC 41-694-04), ecoFIT PURE 618 - VU 186/6-3 (2016) (GC 41-694-05), ecoFIT PURE 625 - VU 256/6-3 (2016) (GC 41-694-06), ecoFIT PURE 630 - VU 306/6-3 (2016) (GC 41-694-07)
manualmanualVAILLANT appliance manual — ecoFIT PURE 825 - VUW 256/6-3 (2016) (GC 47-044-68), ecoFIT PURE 830 - VUW 306/6-3 (2016) (GC 47-044-74), ecoFIT PURE 835 - VUW 356/6-3 (2016) (GC 47-044-70)
manualmanualVAILLANT appliance manual — ecoFIT SUSTAIN 615 - VU 156/6-3 (2018) (GC 41-694-30), ecoFIT SUSTAIN 618 - VU 186/6-3 (2018) (GC 41-694-31), ecoFIT SUSTAIN 630 - VU 306/6-3 (2018) (GC 41-694-32)
manualmanualVAILLANT appliance manual — ecoFIT SUSTAIN 825 - VUW 256/6-3 (2016) (GC 47-044-71), ecoFIT SUSTAIN 830 - VUW 306/6-3 (2016) (GC 47-044-72), ecoFIT SUSTAIN 835 - VUW 356/6-3 (2016) (GC 47-044-73)
manualmanualVAILLANT appliance manual — ecoTEC 610 VU 10 CS/1-5 (2023) (GC 41-694-45), ecoTEC 615 VU 15 CS/1-5 (2023) (GC 41-694-46), ecoTEC 620 VU 20 CS/1-5 (2023) (GC 41-694-47), ecoTEC 625 VU 25 CS/1-5 (2023) (GC 41-694-48), ecoTEC 630 VU 30 CS/1-5 (2023) (GC 41-694-49), ecoTEC 635 VU 35 CS/1-5 (2023) (GC 41-694-50), ecoTEC PLUS 826 VUW 20/26 CS/1-5 (2023) (GC 47-044-92), ecoTEC PLUS 832 VUW 25/32 CS/1-5 (2023) (GC 47-044-93), ecoTEC PLUS 836 VUW 30/36 CS/1-5 (2023) (GC 47-044-94), ecoTEC PLUS 840 VUW 30/40 CS/1-5 (2023) (GC 47-044-95)
manualmanualVAILLANT appliance manual — ecoTEC PLUS 940 VUI 30/40 CS/1-5 (2023) (GC 47-044-96)
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