Unvented Hot Water Cylinders: Efficient and Reliable Hot Water Solutions


Unvented hot water cylinders have revolutionized the way we store and distribute hot water in homes and businesses. These modern water heating systems offer several advantages over traditional vented cylinders, providing efficient, reliable, and pressurized hot water on demand. In this article, we will explore what unvented hot water cylinders are, how they work, and the many benefits they bring to the table.

Understanding Unvented Hot Water Cylinders

Unvented hot water cylinder, also known as pressurized or sealed cylinders, are a type of water heating system that stores and supplies hot water directly from the mains water supply, without the need for a header tank. They are typically made of high-quality stainless steel, which is highly resistant to corrosion, ensuring the longevity of the system.

How Unvented Hot Water Cylinders Work

  1. Pressure: One of the primary features of unvented hot water cylinders is that they maintain water at mains pressure. This means that the hot water supply is delivered with consistent pressure and flow rate, making it suitable for multiple outlets simultaneously, such as showers and taps.
  2. Heating Element: Unvented cylinders incorporate an electric immersion heater or a coil for connection to a boiler or renewable energy source, which heats the water within the cylinder.
  3. Safety Mechanisms: Unvented cylinders come equipped with safety features like pressure relief valves and temperature relief valves to prevent overheating or excessive pressure buildup.

Benefits of Unvented Hot Water Cylinders

  1. High Water Pressure: The main advantage of unvented hot water cylinders is the delivery of high-pressure hot water, which is especially appreciated for powerful showers and quick-filling baths. This feature provides superior convenience for homes and businesses.
  2. Energy Efficiency: Unvented systems are highly efficient because they heat water directly from the mains supply, eliminating the heat loss that occurs in traditional vented systems. This results in energy savings and lower utility bills.
  3. Space Savings: Unvented cylinders don’t require a cold water storage tank, freeing up space in your property. This makes them a great choice for homes with limited space or for those who wish to maximize storage space.
  4. Continuous Supply: Unvented cylinders can provide hot water on demand, without running out of hot water as long as the heating element has enough capacity to meet the demand. This is particularly useful in busy households and commercial settings.
  5. Reduced Risk of Contamination: With no open vent, unvented cylinders are less susceptible to contamination and pollutants, ensuring the quality and cleanliness of your hot water supply.


Unvented hot water cylinders have redefined the way we experience hot water in our homes and businesses. With their consistent high-pressure hot water supply, energy efficiency, space-saving design, and reliability, they offer numerous advantages over traditional vented systems. Whether you’re renovating your home, building a new one, or considering a water heating system upgrade, unvented hot water cylinders are a modern and efficient choice that can meet your hot water needs effectively and conveniently.