The Joule Invacyl Unvented 300L Direct Cylinder Standard (TRBMVD-0300LFC) is a high-capacity direct-heated stainless steel hot water cylinder designed for unvented mains-pressure systems. With a 300-litre storage capacity and two immersion positions, it provides substantial hot water storage for properties with high hot water demand.
Constructed from corrosion-resistant LDX 2101 stainless steel, the cylinder features dense PU foam insulation with a 50mm foam thickness to help reduce standby heat loss. Designed for mains-pressure operation, it supports a maximum mains water pressure of 10 bar and an operating pressure of 7 bar, while a 25-year warranty provides long-term product support.
300L Capacity
Direct Cylinder
LDX 2101 Stainless Steel
50mm PU Insulation
25-Year Warranty
Applications & suitability
Large family homes
The 300-litre storage capacity is suited to properties with high hot water demand and multiple bathrooms.
Light commercial applications
Suitable for offices and small business premises requiring substantial hot water storage.
Direct immersion heating
Designed for direct electric immersion heating with two immersion positions.
New-build & renovation projects
A high-capacity unvented cylinder solution for new installations and suitable renovation projects.
Key specifications
| Product Model |
Joule Invacyl Unvented 300L Direct Cylinder Standard — TRBMVD-0300LFC |
| Actual Capacity |
300L |
| Unit Weight Empty |
55kg |
| Unit Weight Full |
355kg |
| Cylinder Material |
LDX 2101 Stainless Steel |
| Outer Casing |
Coated Mild Steel |
| Thermal Insulation |
Dense PU Foam |
| Foam Thickness |
50mm |
| Number of Immersions |
2 |
| Immersion Specification |
3kW @ 230V per immersion |
| Maximum Mains Water Pressure |
10 bar |
| Operating Pressure |
7 bar |
| Safety Temperature |
90°C |
| Tested To Standard |
BS EN 50440:2015 |
| Heat Loss |
1.92 kWh/24h |
| Warranty |
25 Years |
Installation & system compatibility
The Joule Invacyl 300L Direct Cylinder Standard is designed for unvented mains-pressure hot water systems and direct immersion heating. It has a maximum mains water pressure of 10 bar and an operating pressure of 7 bar. The cylinder provides two immersion positions, with each immersion specified at 3kW @ 230V. Specific installation dimensions, connection details and system requirements have not been provided in the supplied product information and should be confirmed before installation.
Storage & heating performance
300L hot water capacity
The 300-litre actual storage capacity provides substantial hot water storage for properties with high demand.
Dual immersion positions
Two immersion positions provide direct electric heating capability, with each immersion rated at 3kW @ 230V.
50mm PU foam insulation
Dense PU foam with a 50mm thickness is designed to help reduce standby heat loss.
1.92 kWh/24h heat loss
The supplied specification lists a heat loss figure of 1.92 kWh over 24 hours.
Durability & protection
LDX 2101 stainless steel
The cylinder uses corrosion-resistant LDX 2101 stainless steel construction.
Coated mild steel casing
A coated mild steel outer casing provides additional protection around the cylinder.
25-year warranty
The supplied specification lists a 25-year warranty for long-term product support.
Ideal for
Large family homesSuitable for properties with multiple bathrooms and substantial hot water requirements.
Light commercial premisesDesigned for offices and small businesses requiring high-capacity hot water storage.
Direct immersion systemsSuitable for systems requiring direct electric immersion heating or backup heating capability.
New-build & renovation projectsA high-capacity unvented cylinder option for suitable new-build and renovation installations.
Frequently asked questions
What is the Joule Invacyl Unvented 300L Direct Cylinder?
The Joule Invacyl Unvented 300L Direct Cylinder Standard is a 300-litre direct-heated stainless steel hot water cylinder designed for unvented mains-pressure systems. It features two immersion positions and LDX 2101 stainless steel construction.
What is the capacity of the Joule Invacyl 300L cylinder?
The cylinder has an actual storage capacity of 300 litres, making it suitable for properties with substantial hot water requirements.
How many immersions does the Joule Invacyl 300L have?
The cylinder has two immersion positions. Each immersion is specified at 3kW @ 230V.
What material is the Joule Invacyl 300L cylinder made from?
The cylinder is constructed from LDX 2101 stainless steel, with a coated mild steel outer casing.
What insulation does the Joule Invacyl 300L use?
The cylinder uses dense PU foam insulation with a 50mm foam thickness. The supplied specification lists heat loss at 1.92 kWh/24h.
What pressure can the Joule Invacyl 300L cylinder operate at?
The supplied specification lists a maximum mains water pressure of 10 bar and an operating pressure of 7 bar.
What is the warranty on the Joule Invacyl 300L Direct Cylinder?
The supplied product specification lists a 25-year warranty.
What is the stock code for the Joule Invacyl 300L Direct Cylinder?
The manufacturer product model and stock reference is TRBMVD-0300LFC.
The Joule Invacyl Unvented 300L Direct Cylinder Standard combines 300-litre hot water storage with direct immersion heating, LDX 2101 stainless steel construction and 50mm dense PU foam insulation. Designed for unvented mains-pressure systems, it supports up to 10 bar mains water pressure, includes two 3kW immersion positions and is backed by a 25-year warranty.
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