Not a gret idea. ) c6 z* P. R# D: U& p$ M1 f9 _% V6 Z* H1 w& A. i3 [, ^
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. ' c4 L4 \! ?1 g7 c4 a / B a9 V L" n9 U( p0 Z" ~: \- UBeside,furnace hot water coil is made of metal. Some of it will come into the hot water.