Each model in the new Herald range features a 316L stainless steel heat exchanger that greatly improves resistance to corrosion and is supported by a 10-year warranty. They also offer very low NOx emissions of 39mg/kWh, which means they qualify for the maximum three BREAAM points.
Capable of working at high operating pressures of up to 11bar, Herald boilers are particularly suitable for high rise buildings. They also deliver temperatures up to 88degC and at Delta T of 30degC.
They are particularly compact. At 394mm wide, they are narrow enough to fit through a standard doorway and the largest model, at 228kW output, has a footprint under 0.5m2. At a maximum height of 1080mm they can cope with most headroom restrictions and can fit into the tightest of plant rooms.
Multiple flue options are available including horizontal or vertical concentric balanced flue and also conventional where runs of up to 60m are achievable. The conventional flue outlet connection is at the rear of the unit, which means the Herald is perfectly designed to be a replacement for traditional atmospheric boilers.
All models in the range meet the requirements of the European Energy Related Products (ErP) directive, which came into force last year and encourages replacement of traditional boilers with high efficiency, condensing technology. Two Herald models – the HCB46CE and HCB61CE – are within scope of the directive’s Energy Label requirement and both have ‘A’ classifications.
Herald boilers employ pre-mix burners with 5:1 turndown to closely match demand patterns and enhance operating efficiencies even under part-load conditions. Multiple installations offer further operational benefits as the integral controls include a cascade system. A two-boiler installation, for example, provides a combined turndown of 10:1; and up to eight boilers can be operated in ‘cascade’ providing up to 1.8Mw heat output.
A further feature of the cascade system is that should the ‘lead’ boiler fail for any reason; the controls will automatically adjust the output of the other boilers in the cascade, designating another as lead so there is no interruption to the heating supply.
The integral controls remove the need for a BMS (although connection to a BMS is available). The controls also provide pump modulation in line with operating conditions and weather compensation control and, when used with an indirect hot water cylinder, the system provides a temperature controlled ‘pasteurisation’ process to prevent build-up of legionella bacteria.
This built-in control provision can considerably reduce installation cost and time even when the system is required to manage a number of separate heating zones.
Lochinvar plans to further enhance the Herald range within the next few months by introducing its app-based ‘smart control’ option, which will allow the boilers to be controlled and monitored from mobile devices.