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Plumb2U carries the parts and spares for both instantaneous and storage electric water heaters, from elements and thermostats to the fittings that connect them into a system, at trade prices with next-day despatch across the UK. For merchants and installers working from a plumbers merchants account rather than a shop counter, that means the right spare is one order away, not a special one.
Choosing between an electric shower and a mixer shower is not really a matter of preference; it comes down to what the property's existing hot water system can actually deliver, and the two options make very different demands on it.
An instantaneous electric water heater does not store hot water at all. Cold mains water passes through a heating element on its way to the tap, and the unit's kW rating decides how much temperature rise it can deliver at a given flow rate. Push more flow through it and the water comes out cooler; the physics does not bend. That makes instantaneous units a sensible spec for a single low-demand outlet, a small flat, a static caravan, a workshop sink or a holiday let where two people are never running hot water at once.
Learn more at trade plumbing supplies.
The other practical difference is capacity and recovery. Because an unvented cylinder is sealed and pressurised, it can be built with an immersion element, a coil, or both, and sized to match a property's actual hot water demand rather than what a loft tank happened to allow. That flexibility is a big part of why unvented systems are now specified so widely in new-build and refurbishment work.
None of this is a guide to fitting a shower from scratch; it is a note on the specific parts that keep coming back across the working life of a unit already installed, and worth having in stock rather than ordering one at a time as each call comes in.