Q: In his November 1998 article, "Using Water Heaters for Radiant Heat," Bill Clinton shows how to heat a home with a gas water heater. Will an electric water heater work in this type of system? How about a tankless electric water heater?
Q: After reading the article "Using Water Heaters for Radiant Heat" (11/98), I decided to replace my boiler with a 75-gallon propane water heater. In general, this is working great, except that about every three weeks the pressure-temperature relief valve, which is rated at 210°F, keeps tripping. I live in the cold climate of Michigan, and I need to keep the water heater temperature set on "High," which is about 180-190°F. When the relief valve trips, I notice that the water temperature is about 195°F. What’s going on?
Q: A client wants a portion of a basement slab to have radiant heat to take the chill off the floor of a planned playroom (there will be supplemental heat). The hvac contractor wants the radiant tubing, which will be attached to wire mesh, to be lifted into the middle of the slab during the pour to put the heat closer to the surface. The concrete contractor doesn’t want to do this because he insists that cracks will show up along the tubing. He wants to leave the tubing at the bottom, and says the insulation board will drive the heat up anyway. He recommends at least 3 inches of concrete-above the tubing. Which is correct?