Not a gret idea. ) v6 T* v' }* j0 s( A+ G , |# L! X1 b4 g. A- _6 r0 y$ ?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.; w( |: V7 p" y% h
+ n2 z) V1 z2 s% V) Q: n' wBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.