{HEAD ~ The unburned particulate accumulation} in the exhaust duct of a combustion system, such as the flue lining of a stove, is monitored by {TAIL ~ a circuit} which receives a temperature indicating signal from a temperature sensing device mounted within the duct 
{ HEAD ~ The unburned particulate accumulation } in the exhaust duct of a combustion system , such as the flue lining of a stove , is monitored by { TAIL ~ a circuit } which receives a temperature indicating signal from a temperature sensing device mounted within the duct
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH