My guess is half of what old smokey burnt.
Usually this time of year I wouldn’t have bothered starting the wood boiler yet and just use the waste oil to batch burn and heat 700 gallons of water up as it took too much wood even in the shoulder season. Always ran the oil boiler along wit the wood in the winter to cut down on wood usage, not seeing that being a problem. The G400 heats 700 gallons of water up in practically no time, longest I’ve seen it run has been 20 minutes where the old one might run for hours at a time reheating all that wood.
I get done wit harvest I’m going to rerun my test I did on ole smokey a few weeks ago. I took three hundred pounds of wood, started a fire and let it go, 6 hours later the water temp was starting to drop and the water was only up to 160. I haven’t measured it out for the G400 yet but my guess would be it shut off at 180 before burning half that much, but it also heats the water faster than the fifty FPHE can heat the 450 gallons of water in the waste oil boiler tank, so it cycled on and off several times before the shop water caught up.
We had a pretty cool day awhile back with 30-40 mph winds, I turned the heat all the way up in the house and opened a window or two downwind, turned all the air handlers on in the shop, two fifty thousand and one hundred thousand BTU and left the service door open, the 400 kept up no problem and was cycling on and off. I’m also hoping for some real frigid weather this winter to see what it does, I’ll kick the snow melt on next time as well and see what happens.