Not a gret idea.! B; j( G# c; S" M u) a1 D# [
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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 u: p4 ]5 r) H% x* x/ o
( X" E3 x8 {. P6 k- QBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.