Ariston
Ariston Expansion Vessel 8 Litre 407649
8 litre expansion vessel for the Ariston Compact 400 20/1 MFS boiler, absorbing pressure changes in the heating circuit.
£218.93
£182.44 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 EXPANSION VESSEL - 8 LITRE is an Ariston expansion vessel intended for the Ariston Compact 400 20/1 MFS boiler. It provides a sealed air cushion inside the heating circuit, taking up the expansion of water as it heats. This limits the pressure rise in the system and reduces the load placed on components such as the pressure relief valve.
Signs this part needs replacing
- System pressure climbs sharply when the boiler heats up and drops again when it cools
- The pressure relief valve discharges water during normal running
- The boiler locks out or reports a low pressure fault
- Water appears at the vessel air valve when it is depressed
- The vessel feels heavy or gives no air resistance when shaken
Before you order
- Confirm the appliance is an Ariston Compact 400 20/1 MFS
- Check the capacity and physical size of the existing vessel against this 8 litre unit
- Check mounting and access on the appliance before removal
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ARISTON ARISTON COMPACT 400 20/1 MFS | — | — | — |
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.
No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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