10 bar
Max. Working Pressure
1.5 bar
Factory Pre-Charge
99°C
Max. Operating Temp.
Installation & Compliance
This vessel is WRAS approved for use on potable (mains-fed) water systems and complies with the Pressure Equipment Directive (PED). Always check the pre-charge pressure against your system's static mains pressure before commissioning, and isolate the vessel from the system before adjusting the air charge.
Pre-Charge Note
The factory pre-charge pressure is 1.5 bar across the 50L-200L vertical range. This differs from the smaller 12L-24L wall-mounted Ultra-Pro vessels, which are pre-charged to 3 bar — always confirm the correct model and pre-charge before ordering a replacement.
Serviceable By Design
The butyl/EPDM membrane is fully replaceable, so the vessel body does not need to be replaced if the membrane fails — this significantly reduces long-term maintenance cost compared with sealed, non-serviceable vessels.
Key Features
Food-Grade Membrane
The interchangeable butyl/EPDM membrane keeps stored water separated from the steel shell, preserving water quality and extending vessel life.
WRAS Approved
Certified for use on potable water systems, meeting the water quality requirements for unvented hot water cylinder installations.
Corrosion-Resistant Shell
A MIG-welded carbon steel body with blue epoxy powder coating resists corrosion in demanding plant room environments.
Stainless Steel Flange
The connection flange is manufactured in stainless steel for long-term durability at the water interface.
High Temperature Rating
Rated to 99°C maximum operating temperature, suitable for the elevated stored-water temperatures used in unvented cylinder systems.
PED Compliant
Manufactured to the Pressure Equipment Directive, giving installers confidence in a certified, traceable pressure vessel.
Technical Specification
General
Type
Potable Expansion Vessel
Orientation
Vertical, Floor Standing
Application
Unvented Hot Water Cylinders, Potable Water Systems
Construction
Shell Material
MIG-Welded Carbon Steel
Membrane
Butyl / EPDM, Replaceable, Food Grade
Connection Flange
Stainless Steel
Finish
Blue Epoxy Powder Coat
Performance & Approvals
Maximum Working Pressure
10 bar
Factory Pre-Charge Pressure
1.5 bar
Operating Temperature Range
-10°C to 99°C
Standards
WRAS Approved, PED Compliant
Capacity & Dimension Variants
Capacity
MPN
Diameter
Height (H)
Flange Offset (E)
Connection
50L
1100005006
380mm
770mm
180mm
1" BSP
60L
1100006006
380mm
860mm
180mm
1" BSP
80L
1100008006
450mm
830mm
153mm
1" BSP
100L
1100010006
450mm
910mm
153mm
1" BSP
200L
1100020006
550mm
1235mm
210mm
1½" BSP
Frequently Asked Questions
What size Ultra-Pro vessel do I need for my cylinder?
Vessel sizing depends on the total stored water volume of the cylinder and the incoming mains pressure. As a general guide, a 50L or 60L vessel suits typical domestic unvented cylinders up to around 210-250 litres, while 80L-200L vessels are used on larger domestic or light commercial cylinders. Always check the cylinder manufacturer's expansion vessel sizing chart before ordering.
Is this vessel suitable for a mains-fed unvented hot water cylinder?
Yes. The Ultra-Pro potable range is WRAS approved specifically for use on potable, mains-fed water systems, including unvented hot water cylinders installed under G3 Building Regulations.
What is the factory pre-charge pressure, and can it be adjusted?
The 50L-200L vertical Ultra-Pro vessels are supplied with a factory pre-charge of 1.5 bar. This should be checked and, if necessary, adjusted to suit the site's static mains pressure before the vessel is connected and filled with water. The vessel must be isolated from the system before adjusting the air charge via the Schrader valve.
Can the membrane be replaced if it fails?
Yes. The Ultra-Pro vessel uses a replaceable butyl/EPDM membrane, so a failed membrane can be swapped out without replacing the entire vessel, reducing long-term running costs.
What connection size does the 200L vessel use compared with the smaller sizes?
The 50L, 60L, 80L and 100L vessels all use a 1" BSP connection, while the 200L vessel steps up to a 1½" BSP connection to suit its larger flow requirements.
