The washer pump will pump water at a rate of 15 gallons per minute. Compact washers can pump up only 5 feet. The drain pipe should be a minimum of 1½” I.D. (inside diameter) to assure proper draining. The washer drain hose is 1¼” O.D. (outside diameter).Click to see full answer. Then, what is the maximum height for a washing machine drain?Washing machine manuals typically specify a minimum height of 39” for the entry of the drain hose into the standpipe or faucet box, and a maximum height of 96” (8 feet).Secondly, what size waste pipe do I need for a washing machine? A 2-inch drain pipe is required for all washing machines. The former requirement of 1 1/2-inch pipe is not enough to handle the fast drainage of modern washers. As with all plumbing fixtures and appliances, a washing machine drain pipe must also contain a P-trap. Likewise, people ask, where does washing machine water go? The washer pump forces water from the bottom of the machine into the drain hose. The drain hose loops to the top of the machine, and then down to the drain, enabling the tub to fill. When the water reaches the bend in the hose, it goes out of the drain.What size drain pipe do I need for a washing machine?The standard for new washing machine drain sizes, according to the Universal Plumbing Code, is now 2 inches. The pipe should be between 18 and 30 inches high from the floor, while the P-trap should be between 6 and 18 inches from the floor. These standpipes connect into the home sewage system.