Zilmet Ultra-Pro Potable Expansion Vessel - 50L to 200L

Description

50-200L

Capacity Range

10 bar

Max. Working Pressure

1.5 bar

Factory Pre-Charge

99°C

Max. Operating Temp.

1" / 1½" BSP

Connection

WRAS

Approved

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

Brand

Zilmet

Range

Ultra-Pro

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.

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Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

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