SPECIAL OFFERS
ONYX 5L Potable Vessel ONYX5LPOT
ONYX 5-litre white potable water expansion vessel with a 3/4 inch connection and 2 bar pre-charge.
At a glance
£21.89
£18.24 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 ONYX 5L white potable vessel is a 5-litre expansion vessel with a 3/4 inch connection and a 2 bar pre-charge. It is designed for potable water systems, absorbing the expansion of heated water to limit pressure rise. ONYX expansion vessels are used across cylinder and pressure vessel applications.
Signs this part needs replacing
- Pressure relief valve discharging during heating cycles
- System pressure rising sharply when the cylinder heats up
- Water weeping or corrosion at the vessel connection
- Loss of pre-charge pressure when checked at the valve
- Repeated pressure-related lockouts on the boiler or cylinder
Before you order
- Confirm the connection size is 3/4 inch
- Confirm the 2 bar pre-charge matches the system requirement
- Check there is space for a 5 litre vessel
- Verify the vessel is suitable for potable water use
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| POPULAR CYLINDER SPARES Cold Water Inlet Controls | — | — | — | |
| SPECIAL OFFERS Pressure Vessels & Accessories | — | — | — |
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 documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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