Alpha
Alpha By-Pass Assembly 3.015275
By-pass assembly for Alpha CB and CD series gas boilers, part 3.015275, maintaining primary circuit flow when system demand falls.
At a glance
- Also known as BY-PASS-ASSEMBLY-CB2428, 1250695
£86.06
£71.72 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 by-pass assembly (part number 3.015275) is a hydraulic component fitted to Alpha CB and CD series gas boilers. It maintains a flow path through the primary circuit so water continues to circulate through the heat exchanger when system demand falls or flow is restricted.
Signs this part needs replacing
- Overheat lockouts, or the boiler cycling on its overheat thermostat
- Kettling, banging or rushing noises from the heat exchanger
- Poor heating or hot water performance when demand is low
- Scale, debris or a seized by-pass mechanism found during service
- Water weeping from the by-pass assembly or its connections
Before you order
- Confirm your boiler model and GC number against the fitment list above
- Check that the part number on the existing by-pass assembly matches 3.015275
- Identify whether your appliance is the LPG or natural gas variant where the model listing specifies one
Compliance
| GC number | E65-498 |
|---|---|
| Alternative numbers | BY-PASS-ASSEMBLY-CB2428, 1250695 |
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA ALPHA CB24 | — | — | — | |
| ALPHA ALPHA CB28 | — | — | — | |
| ALPHA ALPHA CD18S | — | — | — | |
| ALPHA ALPHA CD24S | — | — | — | |
| ALPHA ALPHA CD30S | — | — | — | |
| ALPHA ALPHA HE CB25 | — | — | — | |
| ALPHA ALPHA HE CB33 | — | — | — | |
| ALPHA ALPHA HE SY25 | — | — | — | |
| ALPHA CB24 | 47-532-15 | 47-532-15 | — | — |
| ALPHA CB24 (LPG) | — | — | — |
Showing 10 of 20 compatible appliances.
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.
ALPHA appliance manual — CB24 (GC 47-532-15), CB24 (LPG), CB28 (GC 47-532-16), CB28 (LPG)
manualmanualALPHA appliance manual — CD24C (GC 47-532-19), CD24C (LPG) (GC 47-532-29), CD32C (GC 47-532-21), CD32C (LPG) (GC 47-532-30)
manualmanualALPHA appliance manual — HE CB25 (GC 47-532-25), HE CB25 (LPG) (GC 47-532-27), HE CB33 (GC 47-532-26), HE CB33 (LPG) (GC 47-532-44)
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