Choosing the Right Cylinder


Not sure what kind of hot water cylinder to choose for your home? Let us explain the differences and if you want more advice you can talk to our design team to work out a complete home heating solution tailored to you.

Direct and Indirect, what’s the difference?

With direct it’s the cylinder itself that heats the hot water using an immersion heater. If a property doesn’t have access to a gas or oil this can be a solution for getting your hot water.

An indirect cylinder on the other hand has an immersion heater as a back up source only with the primary heat source being an external source of heat. This could be done with a traditional boiler or much more efficiently using either a heat pump or solar thermal. A coil inside the cylinder is heated from the external source and passes this heat over to the water in the cylinder. This water inside the coil re-circulates through the coil but never comes in contact with the water used for the domestic hot water.

What size do need and do I have the space?

Picking the right size cylinder for your needs can be confusing. If it’s too small will I have enough hot water for my home? Too big and am I wasting energy heating all that water. Here is a simple guide to choosing the right size cylinder for your home.

Property Size Bathrooms Cylinder Size
1 Bedroom 1 120-150L
2 Bedrooms 1 150-180L
3 Bedrooms 1 or 2 180-210L
4 Bedrooms 2 210-300L
5 Bedrooms or more 2 300L or bigger

If your worried about space for your cylinder there are options you can choose. A horizontal cylinder may be a better fit for your situation. You could choose a next generation pre-plumbed cylinder from Joule, with a sleek design that reduces the space requirements needed.

To produce a superior cylinder takes a mixture of knowledge, experience, technology, precision and skill. Joule and its owners have been involved in manufacturing cylinders for more than 30 years and over this time we have seen many developments in the manufacturing processes. We are confident today we operate one of the most advanced production facilities supplying cylinders to the European market including the UK and Ireland.