Alpha
Alpha Captive Nut M4 6.8240550
Alpha M4 captive nut, part 6.8240550, for Combi MAX 350 and Combi MAX 600 gas boilers.
At a glance
- Also known as CAPTIVE-NUT-M4, 1251324
Showing prices
£1.98
£1.65 ex. VAT · VAT at 20%
Available to order · 7 working days
Available to order · 7 working days
Not certain it's the right part? The technical team verifies fitment before dispatch — no charge, and it stops a second trip.Call the technical teamSend a technical question
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
The Alpha M4 captive nut is a threaded fastener used in Alpha Combi MAX gas boilers. It provides a fixed M4 thread where access for a separate nut and spanner is restricted. Supplied as part number 6.8240550.
Signs this part needs replacing
- Threads stripped or cross-threaded, so the bolt or screw will not tighten
- Nut spins freely in its housing instead of staying fixed
- Rounded or damaged hex, making it difficult to hold or turn
- Corrosion or rust on the nut or thread
- Fixing works loose repeatedly after tightening
Before you order
- Confirm your boiler is an Alpha Combi MAX 350 or Combi MAX 600
- Check that the thread size required is M4
- Check how many captive nuts are needed for the repair
Compliance
| Alternative numbers | CAPTIVE-NUT-M4, 68240550, 1251324 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| ALPHA COMBI MAX 350 | — | — | — | |
| ALPHA COMBI MAX 600 | — | — | — |
Fitment listings are a guide, not a guarantee. Plant-room assemblies get modified on site more often than not. Send us the GC number off the data badge and a photo of the existing valve and we will confirm before anything is dispatched.
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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