Not a gret idea.& @: {) M; ]1 |# f# O3 b p" J6 Y7 E
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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.2 E+ A9 O% V5 X1 k! v# {% a
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.