Not a gret idea. # U6 N. K) z( h3 O! o6 C P0 t0 h$ A5 X/ Y0 J* @
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.3 p0 ?6 O1 E, ~' A8 N6 p
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.