Viessmann
Viessmann Expansion Vessel CRI 8 7837231
Viessmann CRI 8 expansion vessel, part number 7837231, for Vitodens system and combi boilers.
At a glance
- Also known as 2321306
£183.12
£152.60 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 CRI 8 expansion vessel is a sealed diaphragm vessel used in Vitodens system and combi boilers. It absorbs the volume increase of the heating water as it heats, holding system pressure within the range the boiler expects. It is supplied under Viessmann part number 7837231.
Signs this part needs replacing
- System pressure climbs noticeably as the boiler heats and falls again once it cools.
- The pressure relief valve discharges, or water is seen at the discharge pipe.
- Pressure is lost repeatedly and the system needs frequent topping up.
- Water, rather than air, escapes when the Schrader valve on the vessel is depressed.
- The boiler locks out or reports a low-pressure fault even after the system has been filled.
Before you order
- Confirm the boiler model and serial number against the fit list, as the vessel suits specific Vitodens variants.
- Identify whether the appliance is a system or combi boiler and check the vessel in situ matches the type listed for it.
- Compare the connection and mounting arrangement of the existing vessel with the replacement before removal.
- Cross-check the Viessmann part number 7837231 and the alternative reference VIESMANN7837231 on the existing component or boiler documentation.
Compliance
| Alternative numbers | VIESMANN7837231, 2321306 |
|---|
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| VIESSMANN VITODENS 050-W BPJC 29 KW COMBI SERIAL No. 7537906 | 47-819-31 | 47-819-31 | — | — |
| VIESSMANN VITODENS 050-W BPJC 35 KW COMBI SERIAL No. 7537947 | 47-819-32 | 47-819-32 | — | — |
| VIESSMANN VITODENS 050-W BPJD 29KW COMBI SERIAL No. 7202938 | 47-819-38 | 47-819-38 | — | — |
| VIESSMANN VITODENS 050-W BPJD 35 KW COMBI SERIAL No. 7202939 | 47-819-39 | 47-819-39 | — | — |
| VIESSMANN VITODENS 100-W B1HA 19 KW SYSTEM ERP SERIAL No. 7543420 | 41-819-36 | 41-819-36 | — | — |
| VIESSMANN VITODENS 100-W B1HA 26 KW SYSTEM ERP SERIAL No. 7543421 | 41-819-37 | 41-819-37 | — | — |
| VIESSMANN VITODENS 100-W B1HA 30 KW SYSTEM ERP SERIAL No. 7543423 | 41-819-38 | 41-819-38 | — | — |
| VIESSMANN VITODENS 100-W B1HA 35 KW SYSTEM ERP SERIAL No. 7543425 | 41-819-39 | 41-819-39 | — | — |
| VIESSMANN VITODENS 100-W B1HC 19 KW SYSTEM SERIAL No. 7570671 | 41-819-40 | 41-819-40 | — | — |
| VIESSMANN VITODENS 100-W B1HC 26 KW SYSTEM SERIAL No. 7570672 | 41-819-41 | 41-819-41 | — | — |
Showing 10 of 36 compatible appliances.
Documents & drawings
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