Your Wood Stove Pipe Is Wasting a Water Heater's Worth of Heat. I Caught It With $40 of Copper

Your wood stove pipe sends a water heater's worth of heat up the chimney every two and a half hours of fire, so here's the $101 copper coil build that gave me 118°F hot water with no pump and no power. I'm Clarence, 44 years fixing farm machinery in southern Indiana. In this video I show the copper coil on the outside of the stovepipe, the thermosiphon that moves the water, and the real thermometer readings from a 24°F January Saturday. Materials and cost: 20 ft of 3/8 soft copper tubing $41, 8 ft of 250°F car heater hose $17, brass adapters $11, stainless clamps $17, pipe thermometer $15. Total about $101, plus an old electric water heater tank with the wiring pulled and a five-gallon bucket for the vent. The principle: hot water is lighter than cold, so it rises on its own. That's a thermosiphon, and it only needs heat underneath and a clear path. Safety: never close the system. No valves between the coil and the tank, no lid on the vent, because trapped water that flashes to steam can blow the whole thing apart. Water first, fire second. Drain the coil if it's going to freeze. Keep the tank 3 feet from the stove and put a carbon monoxide detector near it. 0:00 — The heat my stovepipe threw away 0:37 — Who I am and what this won't do 1:01 — How much heat is up that pipe 1:33 — Why the coil goes outside the pipe 1:51 — How water climbs without a pump 2:34 — Materials and the $101 cost 3:13 — Piece one: the coil 4:03 — Piece two: the tank 4:29 — Piece three: the lines 4:50 — Piece four: the vent 5:44 — The height step almost nobody teaches 6:12 — My first try gurgled and banged 6:30 — The test: 24°F, thermometer readings 7:22 — The honest part: what it won't do 7:54 — Safety 8:44 — Outdoor wood boiler vs. this 9:24 — Back in '78 9:57 — The night heat battery (next video) 🔔 If you'd like to be ready before you need it, subscribe and stay with me:    / @clarencebooneof   First water out of this tank, what's it for: dishes, a bath, or the stock tank? Tell me in the comments. I read every one. Builds shown are for general information. Use common sense, follow local codes, and never run fuel-burning devices indoors.