Combustion Blower Speed

Does the combustion blower motor only operate at one speed? Was just curious because I don't hear the speed changing like the convection blower does. I do understand the combustion motor must run at a minimun speed to keep the coal going, but just want to know if it is variable. Thanks

Combustion blower runs full-speed, full-time with the Coal-Trol... No variable....

There is no speed control on the Combustion Blower. It burns up better with Full blower.
The Convection blower and stoker will vary with Feed Rate/Temps, etc....

WNY wrote:There is no speed control on the Combustion Blower. It burns up better with Full blower.
The Convection blower and stoker will vary with Feed Rate/Temps, etc....

Thanks Dave.....Another note....I got my duct hooked up on my hearth. The temperature blowing out the register I just installed upstairs is over 120. How high a temperature can It run before I have to worry?

Most inline duct fans are rated for up to ~ 160 - 180 degrees F. Most hot air furnaces will have the high limit set for ~ 180 to 200 degrees F. Unless you have plastic duct work you should be OK at anything less than ~ 170 degrees F. Of course answering any question such as this remotely is an opportunity to not understand all the facts, so a little common sense is in order to verify that there are no materials in or around the duct that will be negatively affected by that temperature. I hope this helps a little.