Not a gret idea.# f* P7 l0 M W" Z
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Hot water has went through all your home's internal pipes whereas cold water comes "direct" from your local reservoir. Which should be pretty safe.: C- l0 h# X: x6 C* I
|' j9 _: l6 ^/ C* {$ NBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.