Originally Posted by 714Greg
Jim Iím not an expert by any means but the air you blow through the lines goes where the water was including the hot water unit. So my theory when you open each of the hot water faucets that air is going through the hot water unit as well so in my humble opinion that is blowing out the unit. The first time I blew out mine I let the unit fire. Then I turned it off. I usually run through each faucet a couple times just for good measure . They suggest you leave the faucets open to allow for expansion of any residual water.
Thank you for that.
Still looking for where that air goes in, though. I'm betting it's that little rubber pigtail or whatever, but I'll wait for more advice.