Navien
Navien Screw Flat Head Taptite M4 x 10 S18A 20042708A
M4 x 10 flat head Taptite screw in S18A, used across Navien LCB 700 and NCB300/NCB500 series boilers.
£3.91
£3.26 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 Navien flat head Taptite screw, M4 x 10, in S18A, is a fixing specified for Navien LCB 700 and NCB300/NCB500 series boilers. Taptite screws form their own thread as they are driven, so they are used where a component is secured into a prepared hole in the parent material. It is a service fixing for retaining covers, brackets and internal components during repair and reassembly.
Signs this part needs replacing
- The head is rounded or cammed out and the screw can no longer be driven
- Threads are stripped or cross-threaded in the parent material
- Corrosion or rust is present on the head or shank
- The fixing is missing after a previous service or repair
- The screw will not hold torque and backs out under vibration
Before you order
- Confirm the appliance model and serial number against the fit list
- Check the existing fixing is M4 x 10 with a flat head
- Check how many fixings the job requires
- Check the thread in the parent material is sound before refitting
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| NAVIEN LCB 700 COMBI EXTERNAL 21KW (Serial Number 1705) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 21KW (Serial Number 1705) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 28KW (Serial Number 1710) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 28KW (Serial Number 1710) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 36KW (Serial Number 1709) | — | — | — | |
| NAVIEN LCB 700 COMBI EXTERNAL 36KW (Serial Number 1709) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 21KW (Serial Number 1704) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 21KW (Serial Number 1704) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 28KW (Serial Number 1706) | — | — | — | |
| NAVIEN LCB 700 COMBI INTERNAL 28KW (Serial Number 1706) | — | — | — |
Showing 10 of 48 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.
NAVIEN appliance manual — LCB 700 COMBI EXTERNAL 21KW (Serial Number 1705), LCB 700 COMBI EXTERNAL 28KW (Serial Number 1710), LCB 700 COMBI EXTERNAL 36KW (Serial Number 1709), LCB 700 COMBI INTERNAL 21KW (Serial Number 1704), LCB 700 COMBI INTERNAL 28KW (Serial Number 1706), LCB 700 COMBI INTERNAL 36KW (Serial Number 1708), LCB 700 REGULAR EXTERNAL 21KW (Serial Number 1474), LCB 700 REGULAR EXTERNAL 28KW (Serial Number 1478), LCB 700 REGULAR EXTERNAL 36KW (Serial Number 1482), LCB 700 REGULAR INTERNAL 21KW (Serial Number 1472), LCB 700 REGULAR INTERNAL 28KW (Serial Number 1477), LCB 700 REGULAR INTERNAL 36KW (Serial Number 1481), LCB 700 SYSTEM EXTERNAL 21KW (Serial Number 1471), LCB 700 SYSTEM EXTERNAL 28KW (Serial Number 1476), LCB 700 SYSTEM EXTERNAL 36KW (Serial Number 1480), LCB 700 SYSTEM INTERNAL 21KW (Serial Number 1434), LCB 700 SYSTEM INTERNAL 28KW (Serial Number 1475), LCB 700 SYSTEM INTERNAL 36KW (Serial Number 1479)
manualmanualNAVIEN appliance manual — NCB300-28K COMBI - (Serial Number 3710), NCB300-37K COMBI - (Serial Number 3734), NCB300-41K COMBI - (Serial Number 3711)
manualmanualNAVIEN appliance manual — NCB500-1S+/32K COMBI - (Serial Number 3924), NCB500-2S+/41K COMBI - (Serial Number 3712), NCB500-2S/37K COMBI - (Serial Number 3735)
manualNo technical questions yet for this part.
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