SPECIAL OFFERS
Grundfos Watermill Amazon STN-4.0B Brass Universal
Brass universal water boosting pump from the Grundfos Watermill Amazon range, model STN-4.0B.
£763.20
£636.00 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 Grundfos Watermill Amazon STN-4.0B is a brass universal water boosting pump from the Grundfos Watermill Amazon range. It is used to raise water pressure in domestic hot and cold water systems where the gravity-fed supply is insufficient. The universal build suits installations calling for a single unit rather than separate hot and cold pumps.
Signs this part needs replacing
- Outlet pressure at showers or taps drops noticeably below the pump's normal performance
- The pump runs but delivers little or no increase in pressure
- Grinding, humming or excessive vibration from the pump body
- Water weeping or dripping from the pump housing or its connections
- The pump cuts in and out repeatedly, or fails to start at all
Before you order
- Confirm the model number STN-4.0B on the existing pump matches the unit being replaced
- Check whether the installation needs a universal unit rather than a dedicated hot or cold pump
- Verify there is sufficient space and suitable pipework and electrical supply for the replacement to be fitted
- Check the pump's rating and connections against the existing installation before committing
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| SPECIAL OFFERS Grundfos | — | — | — |
Documents & drawings
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No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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