I purchased a hawken gx-10 outdoor wood boiler in the fall of 2014. I was told I would consume roughly 5 cord of wood and only have to fill the unit 1-2 times a day. I actually have burned 9 cord of wood and cant go longer then 6 hours on a load of wood. When the unit was installed, I had purchased 2 heat exchangers. One was for my domestic hot water. The installer said I did not need the heat exchanger for the hot water and he sent it back to the company. I have complained to the company about the minimal burn time on a load of wood and they feel it is because I didn't use the second heat exchanger. can anyone tell me, would the second heat exchanger really help save on wood and give me a longer burn time?