I am in the process of replacing my Irleh 40 and possibly getting a vedolux 37 for my home. I am looking to get 1000gal of storage as well. My home is about 2500 sq ft and I live in northern PA. I figure the heat loss to be between 25K BTU/hr and 50k BTU/hr. I am looking to have my storage last 12 hours in most cases and no less than 8 hours due to my work schedule. So with the peak load of 50K BTU/hr I NEED it to last minimun of 12 hours. Can I accomplish this with the vedolux 37?. I am tempted to go to the larger natural draft boiler from veribronan but I am concerned that I may not have enought draft and there may be more smoke involved inside the house. I am open to other ideas as well. Any advice that is offer will be much apreciated...I look forward to contributing to this foum as I gain more expirience. So far my expirience with my Irleh 40 has not been favorable.