% v3 G5 I v s x0 q- ^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 o* ]' o3 v" f* M d) a- v+ q
" z" \1 K9 W2 x. ?5 l- V0 O& DBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.