lsayre wrote:What are the firebox dimensions of the Harman MKI, MKII, and MKIII?
For comparison, DS Machine's stove BTU's appear to be related to firebox length and width as follows:
L x W x 375 = BTU's
You hit the nail there, it all comes down to firebox size, there's only so much btu's in any given fuel.
The Magnafire SG is on Harman's site listed at the "highest btu coal stove on the market"- by that they must mean hand fed free standing, because there are stokers higher rated than that- don't know if that's true anymore, but it's rated at 120k btu, and will heat up to 5000 square feet. 120k btu is more than a furnace, that's a big hand fed stove. Here's the info from their site.
Front Width: 20-1/2
Viewing Area: 8-1/2 x 4-1/2
BTU/Hour Input: 120,000
Heating Capacity*: 1,900 - 5,000 sq ft.
Magnafire SF Coal Stove
The Magnafire SF-250 Coal Stove is a true workhorse. It’s loaded with features to help you squeeze the most out of your fuel. An optional heat collector works to send hot air out into hard-to-heat places—or lets you tie into an existing system.
•120,000 BTUs — heats 1,900 to 5,000 square feet, based on climate and home efficiency
•Up to 24 hours of burn time on one load of coal
•Harman Grate System extends heating by completely burning coal to fine ash
•Highest BTU coal stove on the market
here's the Mark III
MAGNAFIRE MARK III
Front Width: 25
Glass Size: 14-15/16 x 8-1/2
BTU/Hour Input: 92,000
Heating Capacity*: 1,900 - 4,900 sq ft.