Alpha
Alpha Expansion Vessel 8 Litre 6.4009031
8 litre expansion vessel for Alpha Solar Smart and Secura 4200 appliances, part number 6.4009031.
At a glance
- Also known as EXPANSION-VESSEL-8-LITRE-Z1-11H0000803, 1260834
£70.20
£58.50 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 Alpha 6.4009031 is an 8 litre expansion vessel used in Alpha Solar Smart and Secura 4200 appliances. It absorbs the expansion of heated water within a sealed system, limiting pressure rise and protecting other components from excess stress.
Signs this part needs replacing
- System pressure rises sharply when the appliance heats up
- Pressure relief valve discharges water during normal operation
- Boiler or cylinder pressure drops repeatedly and needs topping up
- Vessel feels heavy or waterlogged when removed
- Water escapes from the vessel's air valve when the core is depressed
Before you order
- Confirm your appliance model against the fitment list above
- Check the existing vessel's capacity and connection type match before removal
- Isolate and depressurise the system before draining the vessel
- Confirm whether the vessel is fitted internally or remotely on your installation
Compliance
| Alternative numbers | EXPANSION-VESSEL-8-LITRE-Z1-11H0000803, 64009031, 1260834 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA SECURA 4200 | — | — | — | |
| ALPHA ALPHA SOLARSMART 100 CYLINDER | — | — | — | |
| ALPHA SOLAR SMART 90 | — | — | — | |
| ALPHA SOLAR SMART UNVENTED KIT | — | — | — |
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 technical questions yet for this part.
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