Arrived onsite forr no heat service call. Found the system off. Tried starting it but found faultnin the combustion and ignition safety system. Provided options to the homeowner. She selected Silver repair. Preformed repair including an burner cleaning and combustion analysis test. System flue exhaust pipe is onthe hotter side but within specifications. The carbon monoxide is 30ppm this is within the safe range but it bordering on high. Note the blower wheel or motor is making some noise but functional. System is operational but recommend replacing due to age and condition.