Unvented Cylinders
Unvented cylinders are designed to work at a high pressure and offer superior flow rates. This is beneficial as it allows high water pressure for a power shower and the ability to feed several outlets.
We manufacture unvented cylinders in both copper and stainless steel which both offer their own unique advantages.
Unvented cylinders have no need for a cold water feed tank and with it being supplied directly from mains water, it offers far greater flexibility than a traditional vented unit. With the unit not requiring a gravity feed or pump it can be placed anywhere in the premises.
Unvented cylinders also have the flexibility to work on a wide variety of systems; they can be fitted with coils for solar heating, heat pumps and underfloor heating. As all units are manufactured in-house, they can be made to bespoke customer specifications such as tapping size and positioning.
A range of standard sizes and formats is available in the Size and Specification tab. Alternative heights from 600mm to 2000mm and diameters from the list are also available where space and water volumes are at a premium.
Interested in purchasing an Unvented cylinder?
Copper
Private water sources however, tend not to be neutral, so cylinders in either material can corrode prematurely.
Stainless
Private water sources however, tend not to be neutral, so cylinders in either material can corrode prematurely.
| Primary Max Working Pressure | 3.5 BAR |
| Pressure Reducing Valve Pre-Set | 2.1 BAR |
| Expansion Relief Valve | 3.5 BAR |
| Combined Temperature & Pressure Reducing Valve | 4.5 BAR |
| Max Working Pressure | 3.5 BAR |
| Max Water Pressure (Before PRV) | 12 BAR |
| Immersion Heater Rating | 3kw 240V AC |
| Pressure Reducing Valve – Max Inlet | 12 BAR |
| Operating Pressure | 3 BAR |
| Expansion Vessel Charge Pressure | 3 BAR |
| Expansion Relief Valve Setting | 6 BAR |
| Pressure & Temperature Relief Valve – Pressure Setting | 7 BAR |
| Pressure & Temperature Relief Valve – Temperature Setting | 90°C |
| Energy Cut-out Thermostat Setting | 80°C |
| Primary Heat Exchanger – Max Working Pressure | 6 BAR |
| Solar Heat Exchanger – Max Working Pressure | 6 BAR |
| Immersion Heater Rating | 3Kw – 240V AC |
Coils
We utilise a high surface area finned copper tube in our copper unvented cylinders for use with a Solar or Heat Pump system which operate at a lower temperature, and a stainless convoluted tube with our stainless steel cylinders. As the stainless tube does not have as high surface area, we utilise a larger coil to match the surface area of its copper counterpart.
Combined Pressure Reducing Valve & Expansion Valve
Reduces the pressure of the incoming cold water feed to 3.0 BAR as well as allowing connection of an expansion vessel.
Temperature & Pressure Relief Valve
Set to relief pressure should the tank reach 7.0 BAR or 90°C.
Expansion Vessel
Supplied at a suitable size relative to unit volume; contains an internal rubber expandable membrane to facilitate increase and decrease of pressure inside the cylinder.
Plastic Tundish
Allows for audible and visual inspection of water being expelled from the pressure relief valve indicating a fault.
Immersion Heater
Electric immersion heater to provide backup heating, available in 3, 6, 9, and 12kw.
Dual Thermostat
Combined high limit and control thermostat for use with a boiler system.
Single Check Valve
Spring-loaded non-return valve to prevent backflow.
Drain Valve
Allows for easy drain down of the tank without needing to remove the cold feed pipe. Useful for when replacing immersion heaters.