Not a gret idea. 1 h9 h4 b- g7 G; L - U7 C; A t& p! M3 g. W( H1 v. 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.4 h# f' q( Y& N* |2 t
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.