Not a gret idea. $ s1 a/ G9 n2 L3 g& p2 _! I m5 E / a+ p, P- P, K$ k3 O7 A+ `) `3 \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.8 q, l: ?6 O2 [; L, M+ t- O
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Beside,furnace hot water coil is made of metal. Some of it will come into the hot water.