System schematic of a seald system with a gas boiler, two radiator zones, an underfloor heating zone and a domesitc hot water (DHW) cylinder.
The NRG Zone 4 manifold ensures that the boiler receives the coldest possible return water so that it is working under optimum conditions and with optimal efficiency. This is especially important for condensing boilers as it greatly increases the likelihood of the boiler operating in condensing mode, which is by far the most efficient. The manifold also ensures that the central heating zones and the DHW cylinder have access to the warmest possible water for their flow. The manifold also provides the system with a full bypass, meaning that the boiler can always maintain its optimal flowrate.