Plant Room Design

It’s essential that the plant room in which the biomass boiler and all the related equipment sits is fit for purpose.

Plant rooms must be watertight, with any penetrations made for pipework, flues, power connections, augers, etc… made good following installation.

Vents for combustion air should be provided for biomass boilers and these should be designed and positioned in such a way as to prevent excessive water ingress, even in high winds.

Some farm and estate customers have historically used barns, outhouses or other similar structures to house biomass boilers, often with the plant room left open to the fuel store (particularly when the fuel is woodchip).  This is bad practice, and not only constitutes a possible fire risk, but also usually results in considerable quantities of dust building up on the boiler and other items of plant. This has implications for cleaning and maintenance, and in extreme circumstances, dust ingress to control panels and other electrical components can result in component failure and can constitute a fire or even explosion risk.  Plant rooms should be sealed against dust ingress to prevent these issues.

One design issue which is often overlooked with biomass boilers is the provision of adequate free air for combustion via vents in the plant room, as failing to provide sufficient free air can restrict combustion, impacting on boiler output and efficiency.  All boiler manufacturer literature should provide reference values for combustion air, often expressed as n2 cm per kW of boiler capacity. Vents or louvres should be provided at high and low level, and position in such a way as to make it difficult or impossible for them to be obstructed at a later date – plant rooms are often used for storage once owners realise that they are warm, out of the way places.