Unvented Hot Water Cylinders
What are the Benefits of Unvented Cylinders
Unvented cylinders are basically hot water cylinders that source water directly from the main water supply, heat it up using electricity, and supply it to the main water line at a high pressure. An unvented cylinder typically holds water at a very high pressure (between two to three bar), making it possible to supply outlets placed at a higher elevation with relatively strong flow of water.
Advantages of unvented pressurised cylinders
1. Can be placed at lower levels in the water supply.
Because of the high pressure in an unvented hot water cylinder, it can be placed freely in the water supply. You can even place it in a loft away from the main pipework and use it to supply water to higher levels with the same pressure and speed as water from the main supply.
2. Reduces pipework
Unvented cylinders are fed directly by the main water line. Thus, there is no need to maintain a separate cold water tank. This reduces pipework to a minimum. You also do not need any additional tanks to separate hot and cold water supply.
An unvented water cylinder may be made from copper or stainless steel. Stainless steel is stronger than copper and is more appropriate for higher pressure cylinders. For even higher pressure operation, glass lined steel cylinders can be used.
Since the cylinder feeds directly off the main water supply, it requires a sufficient level of pressure in the main line (at least 2 bar). Most cylinders typically utilize a Pressure Reducing Valve to ensure water at the right temperature is allowed inside the cylinder.
Installing an unvented water cylinder in the main water line is fraught with risk and is not recommended even for seasoned DIY enthusiasts. For best results, get in touch with your local plumber.
An unvented hot water cylinder can ease up the burden on your main water line and remove the need for keeping separate water tanks. This not only frees up space, but also reduces expenses. For homes that need to transfer water to a higher elevation, unvented pressurised cylinders are an ideal choice.