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Two stage GFAs and inefficiencies
I've been hearing that two stage GFAs are not all they are cracked up to be and that low fire efficiencies are much lower due to lower HE temps and blower cool down. Is it as simple as jumping w1 and w2 to keep in high fire? Is a delay needed?
Reason I ask is that I am oversized after a second Man J and would be just about perfect if I could snag low fire btu outputs off two Heil GFAs, 100k and 60k input, or keep in low fire state if someone can convince me its the right thing to do.