Because I didn't do it,lol I had to go to summit to get the 4th fuel line fitting[-6 an straight to -6 an] for the regulator I lost along with the heat exchanger fittings 1/2 npt to -12. and that will go on after this winter so I learn how to drain it for the winter.The blower is back on and running after 3yrs n/a,YAY Go to the 2min 4 startup