Drainage, Waste & VentQuestion 119 of 360
A residential clothes washer standpipe is assigned what DFU value and minimum trap size?
a.1 DFU, 1-1/2 inch
b.3 DFU, 2 inch
c.2 DFU, 2 inch
d.2 DFU, 3 inch
Explanation
A domestic clothes washer standpipe is assigned 2 DFU and requires a minimum 2 inch trap and standpipe to handle its rapid pump-out discharge. A 1-1/2 inch trap is too small for a washer, and neither 1 DFU nor 3 inch matches the code value for a residential washer.
Law Reference: 2022 California Plumbing Code (CPC) §702.0 (Table 702.1)Practice all 360 questions free — no signup required.
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