Cylinders

As a rough guide, allow around 35-45 litres per person for a household with a mains combi top-up, or more if you're running a heat pump with lower flow temperatures. A typical family of four is well served by a 180-210 litre cylinder, while larger properties or those with power showers should look towards 250-300 litres. If in doubt, size up slightly — running out of hot water is a far more common complaint than having too much.

A direct cylinder heats water using an internal electric immersion element and is suited to properties without a boiler, or as a standalone solution. An indirect cylinder has a coil inside connected to a boiler or heat pump, which heats the stored water via a heat exchanger — this is the standard setup for most gas, oil or heat pump central heating systems. Indirect cylinders are generally more efficient to run where a boiler is already present.

Yes, several models in this range — including certain Kingspan Albion Ultrasteel units — are specifically designed or suitable for heat pump systems, with larger coil surface areas to work efficiently at the lower flow temperatures heat pumps produce. If you're specifying for a heat pump installation, check the coil size and cylinder's stated compatibility before ordering, as not every indirect cylinder performs well in this application.

Slimline cylinders have a reduced diameter and are designed for airing cupboards or utility spaces where floor area is tight. Horizontal cylinders lie on their side and are useful where ceiling height is restricted, such as in lofts or under-stair cupboards. Both perform the same job as a standard vertical cylinder but give installers flexibility where space is at a premium.

Yes — unvented cylinders (like the Megaflo range) must be fitted by a G3-qualified installer under Building Regulations Part G, as they operate under mains pressure and require correctly specified safety devices such as expansion vessels and pressure relief valves. This isn't optional; installing one without the right qualification is a building regulations breach. Always confirm your installer holds a current G3 certificate before work begins.

Most cylinders in this range are manufactured from grade 316 or duplex stainless steel, chosen for its resistance to corrosion and scale build-up compared with older copper designs. Stainless steel cylinders typically carry longer warranties — often 20 years or more on brands like Ultrasteel — reflecting their durability in normal domestic water conditions. In hard water areas, descaling or a scale-reducing device is still worth fitting to protect performance long term.