CIBSE issues warning on biomass boilers
CIBSE has become aware of potential hazards in some biomass boilers when operating in slumber mode. The concern is that partial combustion might occur — generating unburned flue gases, including carbon monoxide. The institution is working to provide further guidance. In the meantime the following advice is offered.
It is important to ensure that the carbon-monoxide concentration cannot rise above the lower explosive limit. If the flue is fan assisted, it is important to make provision for the safe removal of flue gases if the fan or its power supply should fail.
The boiler’s fire door should never be opened when the boiler is operating in slumber mode to avoid an inrush of air which might cause a flashover explosion.
The final advice is to ensure that the fuel used is within the specification required by the boiler.