I tried to post this in thread, but keep getting forbidden. sigh. As an update on the blower issue, I have done some more research, talked with one of the engineers that I work with that has done air balancing on ovens, and have come up with some helpful information. I contacted Kayne and sons about the blowers they have, which by the way will do the job in SPADES. The one piece of nomenclature that seems out of place is the way these blowers are rated with regard to static pressure. Static pressure should be rated in inches of water column. So the rating of the blowers in ounces of static pressure is deceptive. They did reply to my inquiry and stated that the manufacturer rated them that way. After 78sharpshooter posted his comment about having to choke his blower down so far, got me thinking about the nomenclature issue with the rating. I think the sp listed can be converted directly to PSI, and that in turn can be converted to water column. going on that premise, the large 164 CFM blower that 78ss has would have 2.5 lbs. PSI of output, that would translate to about 70 inches of water column pressure, which would explain why he has to choke it down so much, if the requirement of a ribbon burner is a minimum of 5 and 7.5 works better, then the wide open 70 that is available will totally exceed the requirement. On a side note, because of the way centrifugal blowers are choked with the inlet being partially ( or mostly ) covered, the motor doesn't have to work as hard, because the impeller is spinning in a negative environment. The reason this works is because the motor doesn't rely on the impeller for air circulation, it has it's own fan for that. As you can see, this is why speed controls don't work well with this type of blower, the motor can't get proper cooling at the lower speeds / higher current that use of a speed control will cause. If anyone has more knowledge about this than I do, please weigh in. These are conclusions I have reached through my research and from the real world experience with this set-up that 78ss presented in his post. Thanks! Storm