Glow-worm
Glow-worm Non Return Valve 05738400
Non-return valve for Glow-worm Xtramax and Saunier Duval Isomax F28 E2 gas boilers.
£14.70
£12.25 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 non-return valve is a hydraulic component used in Glow-worm Xtramax and Saunier Duval Isomax F28 E2 gas boilers. It prevents reverse flow through the water circuit, keeping flow direction correct within the appliance. It is supplied under manufacturer part number 05738400.
Signs this part needs replacing
- Water passing back through the circuit when it should be held in one direction
- Persistent flow noise or water movement heard when the appliance is idle
- Reduced or inconsistent flow at outlets served by the boiler
- Leaks or weeping from the valve body or its connections
- Scale or debris build-up causing the valve to stick open
Before you order
- Confirm your appliance model against the fitment list above
- On Isomax F28 E2, check the serial number against the FROM and UPTO entries
- Check the existing valve for the manufacturer part number before ordering
- Inspect the surrounding pipework and seals for damage that may also need attention
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| GLOWWORM GLOWWORM XTRAMAX | — | — | — | |
| GLOWWORM XTRAMAX | 47-047-15 | 47-047-15 | — | — |
| GLOWWORM XTRAMAX HE | 47-047-29 | 47-047-29 | — | — |
| SAUNIER DUVAL SAUNIER DUVAL ISOMAX F28 E2 FROM SERIAL No 0400197003 | — | — | — | |
| SAUNIER DUVAL SAUNIER DUVAL ISOMAX F28 E2 UPTO SERIAL No 0400197003 | — | — | — | |
| SAUNIER DUVAL SAUNIER DUVAL ISOMAX F28E | — | — | — |
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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