Alpha
Alpha Hydraulic Assembly Complete 3.018099
Complete hydraulic assembly for Alpha CD12S, CD20S and CD28S LPG boilers, performing the diverter valve function.
At a glance
- Also known as HYDRAULIC-ASSEMBLY-COMPLETE-CD28S, 1258137
£338.96
£282.47 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 3.018099 is a complete hydraulic assembly for Alpha CD series LPG boilers. It forms part of the boiler's hydraulic circuit and performs the diverter valve function, directing water between the heating circuit and the domestic hot water circuit. It is listed as a gas boiler spare for the CD12S, CD20S and CD28S LPG models.
Signs this part needs replacing
- Domestic hot water runs cold or fails to reach temperature
- Radiators warm up when only hot water is drawn
- Boiler does not switch cleanly between heating and hot water modes
- Water leaking from the hydraulic assembly area
- Reduced or intermittent hot water flow
Before you order
- Confirm your boiler model and GC number against the fitment list above
- Check the part number on the existing component matches 3.018099
- Confirm the boiler is the LPG variant, as listed
- Isolate the power and water supply and drain down before fitting
Compliance
| Alternative numbers | HYDRAULIC-ASSEMBLY-COMPLETE-CD28S, 1258137 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA CD20S | — | — | — | |
| ALPHA CD12S | 41-532-16 | 41-532-16 | — | — |
| ALPHA CD12S (LPG) | 41-532-17 | 41-532-17 | — | — |
| ALPHA CD20S | 41-532-18 | 41-532-18 | — | — |
| ALPHA CD20S (LPG) | 41-532-19 | 41-532-19 | — | — |
| ALPHA CD28S | 41-532-20 | 41-532-20 | — | — |
| ALPHA CD28S (LPG) | 41-532-21 | 41-532-21 | — | — |
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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