X2 What 3'senough said. I did my 321RLTS today. The setting for sanitizing was 1&4 on the panel. I have 5 low point drain valves accessible in the right front of the basement. 2 are on the right inside the compartment and the other 3 are on the left to the left of the wiring panel. The tank drain is left rear behind the rear wheel. If you have trouble getting suction, reverse the screen so that the screen is inward holding the little valve in the inlet open.
Married To The Navigator
2005 Red GMC Duramax 4X4 HD Crew Cab
4" Magnaflow, Banks Air Intake
Firestone Ride Rite Air Springs