SPECIAL OFFERS
Special Offers ONYX 80L Red Heating Vessel ONYX80LHEAT
ONYX 80 litre red heating expansion vessel rated 1 1.5 Bar for sealed heating systems.
At a glance
£87.55
£72.96 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 80L Red Heating Vessel is an 80 litre expansion vessel from the ONYX range, supplied under the Special Offers pressure vessels and accessories listing. It is intended for use on sealed heating systems, where it absorbs the expansion of heated water and limits the pressure rise as the system reaches temperature. The red casing identifies it as a heating-side vessel rather than a potable water unit.
Signs this part needs replacing
- Water weeping from the pressure relief valve as the system heats up
- System pressure rising quickly when hot and falling sharply when cold
- Filling loop used regularly to top the system back up to pressure
- Water, rather than air, escaping when the vessel valve is briefly checked
- Vessel feels heavy or sounds full of water when tapped
Before you order
- Confirm an 80 litre vessel suits the system volume and the manufacturer's sizing guidance
- Check the stated pressure rating against the design pressure of the installation
- Compare the connection size, thread and orientation with the vessel being removed
- Measure the available space to confirm the replacement vessel will fit in position
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| 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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