Not a gret idea. 3 e( Y9 e2 X: O) N- _( Y9 S" F! ~
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. : ]$ Y# ]- k( Z2 j. l! t- H( \" |$ \( g/ a# c0 A
Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.