Cimm 12 Litre Central Heating Expansion Vessel (8312/ISP)
Every time a sealed heating system heats up, the water inside expands — and without somewhere for that expansion to go, you get pressure spikes that strain the boiler, stress pipework joints and shorten system life. The Cimm ERE 12 absorbs that expansion, keeping system pressure stable through normal heating cycles.
Manufactured to PED 2014/68/UE and EN 13831, the vessel is pre-charged to 1.5 bar and rated to a maximum operating pressure of 4 bar, with a working temperature range of -10°C to +100°C. It uses a fixed rubber diaphragm rather than a replaceable membrane, so unlike Cimm's potable water range, this is a sealed-for-life unit rather than one designed for membrane servicing. This is a non-potable vessel and must not be fitted on drinking water systems.
Key Features & Benefits
12 Litre Capacity: Suited to most domestic sealed central heating systems.
Pre-Charged to 1.5 Bar: Ready to fit into standard heating installations.
4 Bar Maximum Operating Pressure: Matched to typical domestic heating system pressures.
Wide Temperature Range: -10°C to +100°C.
Fixed Rubber Diaphragm: Sealed-for-life construction with no membrane servicing required.
Non-Potable: For closed loop heating and refrigeration circuits only, not drinking water systems.
Ideal For
Domestic sealed central heating systems.
Small commercial boiler installations.
Closed loop refrigeration circuits.
Chilled water systems requiring pressure stabilisation.
Why Buy This Product?
An undersized or missing expansion vessel is one of the most common causes of pressure-related boiler faults, and this 12 litre unit is sized to handle normal expansion cycles in a domestic sealed system without over- or under-compensating. The fixed diaphragm means there's no membrane to service — it's a genuine fit-and-forget component. Just remember it's for heating and refrigeration circuits only, not for drinking water systems.
Order the Cimm 12 Litre Central Heating Expansion Vessel online today.
Specification
Cimm 12 Litre Central Heating Expansion Vessel Specification
Manufacturer
Cimm
Model
ERE 12
Standards
PED 2014/68/UE and EN 13831
Capacity
12 Litres
Dimensions (H x Diameter)
325 x 285mm
Connection
3/4" BSP Male
Pre-Loaded
Yes – Pre-Loaded to 1.5 Bar
Max Operating Pressure
4 Bar
Working Water Temperature
-10 to +100°C
Potable Water Use
No – Non-Potable Applications Only
Membrane Type
Fixed Rubber Diaphragm
Application
Sealed Heating System
Product Type
Central Heating Expansion Vessel
Features
Cimm 12 Litre Central Heating Expansion Vessel Features
12 Litre Capacity: Suited to most domestic sealed central heating systems.
Pre-Charged to 1.5 Bar: Ready to fit into standard heating installations.
4 Bar Maximum Operating Pressure: Matched to typical domestic heating system pressures.
Wide Temperature Range: -10°C to +100°C.
Fixed Rubber Diaphragm: Sealed-for-life construction with no membrane servicing required.
Non-Potable: For closed loop heating and refrigeration circuits only, not drinking water systems.
Questions
Reviews
Cimm 12 Litre Central Heating Expansion Vessel Reviews
