Your S&A Oak Hub Heater is just what is says it is. An oak heater with a cast indirect back pipe and quite attractive one I might add.
It is the same as my Glenwood Modern Oak 116. Don't what size firepot it has or what size area you want to heat but they are a well made quality heater stove. I believe one of our new members (pma) has a hub heater in his collection.
Yes, have a Hub Heater in my growing assortment of addictive drugs...I mean...stoves. It's not an Oak though. May share features, not sure. It has similar 'dumper' in the center of the grate [instead of the fork you pull out]
It also has a somewhat freaky double walled ash pit. Not sure if your Oak has this... Here is the official description:"Examine our double walled ashpit, which imparts a movement to the cold air at the bottom of the room, by drawing it through the stove to be heated..."
This stove has an ashpit within an ashpit. Also has a firepit within a jacket [space beteen firepit and jacket going down to outer ashpit] as far as I can tell, it sucked room air into gradualted opening in back of ashpit, up through space between firepit and jacket...and would then enter exhaust through circular grate that was on brim of firepit. [same place holed ring is on Glenwood baseheater]
Anyway: I don't get it. Convoluted effort to suck in room air to have it exit with exhaust. Unless, it works as a baseheater-because the backpipe does also connect to second ashpit. .....sucking exhaust down the grate ring just above firepit, down through second ashpit and up the backpipe? BUT, no switching mechanism on backpipe to redirect flow that I can see.
I'm sure this sounds like jibberish....but the stove does have an amazing oven: lift top dome and there is a stove plate ...but its at the bottom of a inverted dome going deep inside the stove jacket. Could fit a large pot of baked beans...