Not a gret idea. " k% ]4 p; n6 g6 J% K4 A% [- N M: O6 L5 }9 o1 O x8 }0 s0 C9 E
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.! r8 Z6 y6 B3 @. N+ c- M
( @7 B! x, S: S: x; O, g- `Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.