Alpha
Alpha DHW Expansion Vessel 1.018837
Alpha 1.018837 4 litre DHW expansion vessel for CB50, CD50 and Combi MAX 350 boilers.
At a glance
- Also known as DHW-EXPANSION-VESSEL-CB50, 1250249
£160.49
£133.74 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 1.018837 is a 4 litre domestic hot water expansion vessel used on Alpha CB50 and CD50 combination boilers. It absorbs the expansion of heated domestic hot water within the boiler's DHW circuit, limiting the pressure rise on the tap side. It is a manufacturer part listed for the Alpha CB50, CD50 and Combi MAX 350 appliance families.
Signs this part needs replacing
- Boiler pressure rises sharply when hot water is drawn
- Water discharging from the pressure relief valve during hot water use
- Pressure gauge reads high when the boiler is hot and falls when cold
- Water weeping from the vessel body or its connection
- Repeated loss of system pressure
Before you order
- Confirm your appliance model against the manufacturer's parts list
- Check the existing vessel's capacity and part number
- Verify whether your boiler is the LPG variant
- Check access to the vessel and its connection point before ordering
Compliance
| GC number | E85-127 |
|---|---|
| Alternative numbers | DHW-EXPANSION-VESSEL-CB50, 1250249 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA CB50 | — | — | — | |
| ALPHA CB50 | 47-532-18 | 47-532-18 | — | — |
| ALPHA CB50 (LPG) | — | — | — | |
| ALPHA CD50 | 47-532-24 | 47-532-24 | — | — |
| ALPHA CD50 (LPG) | — | — | — | |
| ALPHA COMBI MAX 350 | — | — | — |
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.
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