LG WM3677HW Owner's Manual page 10

Introduction
• In certain conditions, hydrogen gas can accumulate in a hot
water system that has not been used for two weeks or more.
Hydrogen is explosive. Before servicing in such a situation,
allow the hot water source(s) to run for several minutes to
release any accumulated hydrogen.
Do not smoke or use an open flame while doing this!
WM3677HW