Not a gret idea. 4 D5 N- E7 [- a6 p& g. ~, o ( U5 ]7 A9 R5 e) b1 E4 cHot water has went through all your home's internal pipes whereas cold water comes "direct" from your local reservoir. Which should be pretty safe. 7 K2 f N) S, x8 J% m, I% a5 r2 Z1 ~( |* U' u
Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.