Vaillant
Vaillant Expansion Vessel 0020083521
Vaillant expansion vessel 0020083521 for EcoTEC PLUS and VU series gas boilers.
At a glance
- Appliance family: EcoTEC PLUS, VU
- Also known as 1383095
£221.08
£184.23 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 expansion vessel, part number 0020083521, is fitted to Vaillant EcoTEC PLUS and VU series gas boilers. It accommodates the expansion of water as the heating system warms up, limiting the pressure rise within the boiler's heating circuit. A failed vessel allows system pressure to swing and can lead to repeated pressure loss or discharge from the pressure relief valve.
Signs this part needs replacing
- Boiler pressure rises sharply when the heating is running and drops again once it cools.
- Frequent topping up of system pressure, or the boiler locking out on a low pressure fault.
- Water discharging from the pressure relief valve pipework.
- Banging or knocking noises from the boiler as it heats.
Before you order
- Check the appliance data badge and confirm the model and GC number against the fit list above.
- Confirm the part number on the existing vessel matches 0020083521.
- Establish whether the pressure fault lies with the vessel, the filling loop or the pressure relief valve before ordering.
Compliance
| Barcode / EAN | 4024074579954 |
|---|---|
| Alternative numbers | 1383095 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VAILLANT VAILLANT ECOTEC PLUS 415 VU GB 156-2-0H | — | — | — | |
| VAILLANT VAILLANT ECOTEC PLUS 418 VU GB 186-2-0H | — | — | — | |
| VAILLANT VAILLANT ECOTEC PLUS 428 VU GB 286-2-0H | — | — | — | |
| VAILLANT VAILLANT ECOTEC PLUS 438 VU GB 386-2-0H | — | — | — | |
| VAILLANT VU 156 | 41-044-53 | 41-044-53 | — | — |
| VAILLANT VU 186 | 41-044-54 | 41-044-54 | — | — |
| VAILLANT VU 286 | 41-044-55 | 41-044-55 | — | — |
| VAILLANT VU 386 | 41-044-57 | 41-044-57 | — | — |
| VAILLANT VU GB 156/2-0H | 41-044-53 | 41-044-53 | — | — |
| VAILLANT VU GB 186/2-0H | 41-044 54 | 41-044 54 | — | — |
Showing 10 of 20 compatible appliances.
Documents & drawings
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