I have built a wood fired hot tub with a 179 galvanized stock tank and 1/2" OD soft refrigeration copper tubing of 50ft in length. The input inlet (hot water in) is located on the top of the tank while the output inlet (cold water out) is at the bottom. In theory, this should have created a flow when heated with wood. I have gave it multiple tries by placing the most of the coiled tubing somewhat below the tanks water level then raised up the coiled tubing higher to see if that would make any flow happen. No luck so far getting any type of flow. Im wondering what i'm doing wrong here, coil of 50ft too long? Elevation of the coil too high or too low? 50 ft of coil too long? 1/2"OD copper tubing too small of a diameter. I feel like someone in this forum might have ran into the same problem. I'm close to having the wood fired hot tub in action, any help would be appreciated! I will attach a video here to show you my set up.
