I just found this site. Great stuff! This is my first post. I checked the archives / searched the message base and did not find anything directly on this one. I use an outdoor wood furnace to heat both my home and domestic hot water. I did find a thread in which attaching the heat exchanger to the domestic water heater was discussed - I can add a good bit of clarification to that discussion if anyone is still interested.
To the question at hand: the manufacturer of the furnace recently recommended that an anode rod be installed in the furnace. This is easily done by dangling it in the vent. (These units are almost all open system design.) My question is: In order for the anode rod to be effective, does it need to be electrically connected to the tank? When I spoke with the factory rep he said just letting it dangle in the vent tube was all that was needed. However, if I understand what I have been reading on this site correctly, the anode rod must make electrical contact with the water heater in which it is installed. It seems to me that, therefore, by extension, a rod in the tank of my wood furnace would also have to be electrically attached to the tank. Thoughts?
Hello: I'm imagining a wood burning chamber, surrounded by a water holding chamber. The water chamber is likely steel. Anodes will work best where they have a direct line of sight to all steel to be protected. The ideal situation would be a steel sphere with a round ball of anode metal in the very center. There would be no crevices and the metal to be protected would be the same distance all around, so protection would be the same.
There are sacrificial and powered anodes, but no matter, they must be immersed in water and electrically connected to the steel needing protection to work. Dangling an anode in the vent sounds a bit short of that Anodes are commonly used in big water storage tanks.
Anodes are commonly used in big water storage tanks.
