Thermal Store or Unvented?
Choosing Your Next Water Cylinde

Whether you’re building a new home or installing a replacement water cylinder in your current one, you have a lot of choices to make. The right choice will ensure that you and your family have plenty of hot water for bathing and washing up, but the wrong one could mean more than just struggling with too little hot water. Below, we’ll contrast two of your choices – unvented cylinders and thermal store cylinders – to help you make an informed decision.

Unvented cylinders are the most popular option in the UK currently. These systems are sealed, unlike old-style vented cylinders that were open to the air. This protects against potential contamination, but it also means that you’re able to enjoy mains pressure hot water at every tap in the home. Older water cylinder styles were unable to do this because they were gravity-fed, which meant that only taps on the bottom-most floor would have good pressure.

Water flows into the cylinder and is heated, either by a flame if you have a gas-fired system or by an immersion heater if your system is electric. Every use of hot water will drain the level in the cylinder, with fresh water being used to top it up. Fresh water will take time to come up to temperature, though.

Thermal store cylinders are completely different from both traditional vented cylinders and newer unvented cylinders. Rather than being filled with potable water that gets heated and then used, they are filled with water designated only for heating. The cylinder is not emptied when you open the hot tap.

Thermal store cylinders work by transferring heat from the stored water inside to water passing through a heat exchanger in the piping system. It’s technically indirect heating since there is no immersion heater required. Heat transfers from the stored water to the water in the line, which is then delivered to the tap.

Finally, thermal store cylinders can be powered by many different sources. They’re not limited to gas or electricity. Solar, wood-fired boilers, wind turbines, oil, solid fuel like coal, and pellets can all be used with various models (your model must be designed to use a particular type of fuel).

There’s no simple way to decide whether an unvented cylinder or a thermal store cylinder is the better option for your home. Each system has pros and cons and it’s important to make an informed decision. For many UK homes, unvented cylinders offer the reliable operation and mains pressure hot water required.

However, thermal store cylinders can be viable alternatives. If you’re not sure which is the best choice for your needs, contact us at EasyFlow. One of our experts will discuss your hot water usage needs, and the number of people in your family, and then help you decide on the right water cylinder for your needs. All our technicians are also G3 licensed, so we’re able to install and service unvented cylinders. 

We are based in Manchester and serve Greater Manchester, Liverpool, Chester and surrounding areas.