Not a gret idea./ Y7 h; h. E8 y. g/ K1 w( f
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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. + L! V6 v& l4 s5 M 3 P) ?% i% d. R" G% e! b6 LBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.