what would be the most efficient setting for my boiler. It is an oil fired burnham 200k BTU .I live in the north east.
I am not sure I understand the question, do you mean the thermostat setting, or the temperature you should be heating the water to? Most people seem to think the best thermostat setting in the winter is 65-68 and turning it lower during the night. I prefer to run it at a constant temp, with the feeling that it is more efficient to maintain a temp rather than to keep recovering from a lower temp. If you are talking about the running temp of the boiler, just slightly above the temp you want to maintain in the house. Since it is a boiler and not a steam generator the excess heating of the water is not efficient. Steam, or even superheat is very efficient, but since you are not running industrial equipment, you will never achieve the efficiency of steam. so to run at 120-160 would be more than sufficient. Although there are many factors that you should take into account also, just saying that it is a 200,000 btu heater does not give sufficient info it has to be properly sized for your heating volume of the house, and also for the heat loss calculations. What I am saying is that if you have a relatively small house, and is fairly efficiently insulated, average amount of glass, you can operate the boiler at a lower temp than specified and actually save EDIT there are different types of temperature limit switches, some have fixed upper and lower limits, some are asjustable for both limits and range. If you have fixed switches, I would suggest installing the adjustable one and you can lower your upper limit temp.
