Vaillant
Vaillant 181051 Expansion Vessel 10 Litre
A genuine 10-litre rectangular expansion vessel with 3/8" connection for Vaillant ecoTEC and ecomax boilers, part number 181051.
At a glance
- Also known as VAILLANT181051C
- Replacement must be carried out and re-pressurised by a Gas Safe registered engineer
£29.40
£24.50 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 181051 is a genuine 10-litre expansion vessel fitted inside Vaillant ecoTEC and ecomax boilers. It absorbs the extra volume created as water in the sealed heating system heats up and expands, preventing pressure building to a level that would otherwise trigger the boiler's safety valve.
Signs this part needs replacing
- Boiler pressure creeps up repeatedly and needs frequent re-pressurising
- Pressure relief valve discharges more often than normal
- Vessel feels cold on one side and warm on the other when tapped, suggesting a failed internal diaphragm
- Boiler locks out on high pressure faults
Before you order
- Confirm the exact boiler model and year against the data plate, as fitment varies between ecoTEC/ecomax variants
- Replacement must be carried out and re-pressurised by a Gas Safe registered engineer
Compliance
| Alternative numbers | VAILLANT181051C |
|---|
No fitment data held for this part.
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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