Recirculation system, hot water

QUESTION: Last month a person asked about a way to get hot water without wasting so much water. The advice was to install a recirculation system. My question is: Can a recirculation system be installed where the water pipes are imbedded in concrete? My home is on a concrete slab.
M.C. Gress, via email
ANSWER: “Any house can have a recirculation system,” says Vince McDonald of McDonald Plumbing, Heating and Air Conditioning in Sacramento. “The best system has a designated return line,” he says. “This is a pipe that connects at the far end of the house from the water heater and travels all the way back to the water heater. If it is not possible to have this line, or a person does not want to spend the money to have it installed, there are several systems that use the cold water line as the return line. These systems can be installed in any home regardless of construction. Depending on the system, the pump is installed either at the water heater or under a sink at the far end of the home. Some are automatic and others are activated by a switch.”

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