Not a gret idea. % _7 }7 `0 s' d3 H( d ) y* j- Y5 v: O0 J% M# l/ yHot water has went through all your home's internal pipes whereas cold water comes "direct" from your local reservoir. Which should be pretty safe.' _) i9 r7 K1 U" W0 k* j8 Q6 N
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.