Viessmann
Viessmann Membrane Expansion Vessel 7826473
Membrane expansion vessel for Viessmann Vitodens 200-W Wb2B and Wb2C boilers, absorbing thermal expansion in the sealed heating system.
At a glance
- Appliance family: Vitodens 200-W
- Also known as 2320826
£163.01
£135.84 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 Viessmann 7826473 is a membrane expansion vessel supplied by Viessmann for the Vitodens 200-W appliance family. It sits within the sealed heating circuit and absorbs the increase in water volume as the system heats up, keeping system pressure stable. This is the vessel listed for the Wb2B and Wb2C variants of the Vitodens 200-W.
Signs this part needs replacing
- System pressure climbs quickly as the boiler heats and falls again as it cools
- Water discharging from the pressure relief valve during normal operation
- Pressure gauge reading high with no obvious cause elsewhere in the system
- Little or no charge felt when the vessel valve is checked
- Water present at the vessel valve instead of air
Before you order
- Confirm the boiler model and serial number against the fit list above
- Check the existing vessel part number and compare it with 7826473
- Verify the vessel's physical size and connection against the unit being replaced
- Confirm system pressure and vessel charge before and after fitting
Compliance
| Alternative numbers | 2320826 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VIESSMANN VITODENS 200-W WB2B 19KW SERIAL No. 7248823 | 41-819-14 | 41-819-14 | — | — |
| VIESSMANN VITODENS 200-W WB2B 26KW SERIAL No. 7248824 | 41-819-15 | 41-819-15 | — | — |
| VIESSMANN VITODENS 200-W WB2B 26KW SERIAL No. 7248825 | 47-819-09 | 47-819-09 | — | — |
| VIESSMANN VITODENS 200-W WB2B 30KW SERIAL No. 7248826 | 41-819-16 | 41-819-16 | — | — |
| VIESSMANN VITODENS 200-W WB2B 30KW SERIAL No. 7248827 | 47-819-10 | 47-819-10 | — | — |
| VIESSMANN VITODENS 200-W WB2B 35KW SERIAL No. 7248828 | 41-819-17 | 41-819-17 | — | — |
| VIESSMANN VITODENS 200-W WB2B 35KW SERIAL No. 7248829 | 47-819-11 | 47-819-11 | — | — |
| VIESSMANN VITODENS 200-W WB2C 19KW SERIAL No. 7424985 | 41-819-14 | 41-819-14 | — | — |
| VIESSMANN VITODENS 200-W WB2C 26KW SERIAL No. 7424986 | 41-819-15 | 41-819-15 | — | — |
| VIESSMANN VITODENS 200-W WB2C 26KW SERIAL No. 7424987 | 47-819-09 | 47-819-09 | — | — |
Showing 10 of 14 compatible appliances.
Documents & drawings
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