ducting a hotblast 1557m

Toby Taber · Jan 2, 2015

Morning all. I have a question about ducting my new hotblast furnace. My home has two central air units and, therefore had two distribution line for heating and cooling in the home. The furnace had two 8" ports in the top for ducting. Should I run 1 line to each of my trunk lines or split the two 8" into 4 lines, two for each trunk line? Thanks

huffaker · Feb 14, 2015

Without knowing much else about your duct lines, I'd say one for each. They both push out the same volume, it would actually be a better design to have one plenum exiting the top of the furnace. I have a 1557 and love it, contrary to lots of others on here. I get a 12 hour burn and minimal creosote, keep the 2700 sq ft house at 72-76 all winter.

Sent from my iPad using Tapatalk

Toby Taber · Feb 15, 2015

I suppose I should have explained better. The trunk lines (2) are insulated rigid metal, measuring approximately 12" x 24". The lines feeding the registers in the house are 6" insulated flex ( yuck ) and they are stretched pretty tight. The windows are old and drafty, and the floors are uninsulated. On my best day, I can only get 5-6 hours burn times and there are little coals left. How exactly do you get 12 hour burns?

GreaseMnky85 · Feb 15, 2015

I would also love to know how you get 12 hour burn times

brenndatomu · Feb 16, 2015

Toby Taber said:
The lines feeding the registers in the house are 6" insulated flex

Just FYI, all duct work on a wood furnaces needs to be metal.
And if huff is getting 12 hour burns and minimal creosote all while heating 2700 sq ft to 72-76...the government will wanna come n get that thing to study, cause if it is really doin all that, and says Hotblast on it...it's been modded by aliens! :crazy2:

Come to think off it, he never said he was burning wood...I've always heard it said those things were really designed to be coal burners

laynes69 · Feb 16, 2015

Our furnace was terrible at burning coal. I tried both soft and hard coal. I later found that the v shaped firebox is about the worse design you can have. A rectangular firebox with a full set of shaker grates is what is needed for coal. Harman and Hitzer are a couple that are truely designed for coal burning. The only success I had with coal in the hotblast was mixing soft coal with wood or burning lump coal.