Not a gret idea.2 W* k4 B9 \) ]* _% M+ x
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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.) a3 @$ ^0 f! h( ] U3 E
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.