I am getting very warm water out of the cold water tap in the kitchen unless I run the water for 1 minute or so. This happens even in the summer (in fact, it may be worse then).

I am wondering if it has something to do with the gravity hot water recirculation system.

I have a very old, large 3 story house that has a gravity fed hot water recirculation system. As I understand it, the advantage of this system is that it circulates the hot water inside the house so if you are in a distant bathroom and you need hot water, you don't have to run the faucet for 5 minutes to get hot water.

Anyhow, we recently had the basement repiped - they replaced galvanized pipe with copper pipe. The gravity recirculation line seems to have 2 branches. One branch returns to the hot water heater. The other branch seems to be routed back into the cold water line in a spot on the pipe before the kitchen sink line - this would seem to be very inefficient.

Is this common or possible? This would seem to explain why I am getting hot water out of the cold water tap.

Thanks.