Not a gret idea. 8 i& S) y( \2 ~6 q $ T: U x0 q" C- ?- T7 ]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.7 o9 }% e7 A' `$ q
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.