Mixergy smart hot-water cylinders

Mixergy models and systems

Faults we diagnose

A cylinder can be blamed when the actual fault sits in the electrical supply, Economy 7 switching, immersion heater, thermostat, wiring, motorised valve, boiler/heat-pump heat source, pressure controls or discharge arrangement. We test the relevant system before recommending a replacement.

Installation and replacement

For replacement we check usable cupboard space, cylinder capacity, mains pressure and flow, discharge route, direct versus indirect heat source, electrical circuit, immersion strategy and future plans such as solar PV or a heat pump. In London flats we also plan access, leasehold constraints and compact/slimline options where relevant.

Direct electric and Economy 7 cylinders

Direct cylinders commonly use one or more immersion heaters. In an Economy 7 property the lower immersion is often arranged for off-peak heating while an upper immersion provides a boost. If the overnight hot water disappears but boost still works, the fault may be in the off-peak supply, switching, circuit, thermostat or immersion element rather than the cylinder shell.

Unvented safety and servicing

Unvented systems operate with safety controls and discharge arrangements that must remain functional. Servicing is more than checking for leaks: controls, valves, expansion provision and the discharge path are inspected in line with the system type and current manufacturer instructions. We do not bypass safety devices to keep a cylinder running.

Related pages

Manufacturer status

Mixergy smart cylinder behaviour

Mixergy cylinders use active control and stratification to heat the required volume of water rather than always treating the full cylinder as one uniform store. That makes control settings, sensors and connectivity more relevant than on a purely passive traditional cylinder.

When a Mixergy system appears short of hot water, the first question is whether the cylinder is failing to heat or whether the control strategy is only heating part of the volume. We avoid replacing components before the operating mode and heat-source demand are understood.

Integration matters

Mixergy products can be used with different heat sources, so a cylinder fault enquiry should include the connected boiler, immersion or renewable system as well as the tank itself.