All slow combustion woodheaters tend to smoke at light-up or refuelling. However, there is no reason for woodheaters to smoke excessively for long periods of time if they are operated correctly and are well maintained.
Minimising the emission of visible smoke from woodheaters and fireplaces can have substantial health benefits for the community in view of the harmful impacts of wood smoke.
For more information, please go to: http://www.epa.nsw.gov.au/woodsmoke/resources.htm#excessive