[Swimmer]

Couple of years ago I check to see what my Aquastat settings were on my Peerless oild burner, because it seemed like the burner ran to much. The settings were 190/190. After an oil fill-up I told about the 190/190 settings this to the owner of the company. Owner of the company says to set the Aquastat at 160/120 since its summer, and no lower. I do. He swore I wasnt seeing the settings right at 190/190. I was. Now the weather gets colder. The tech comes back to clean again and writes down that he sets the Aquastat at 170/170. I check the Aquastat and its still set at 160/120. Now I am a little pissed. It seems to me even though I am a layman this 190/190 or 170/170 setting is just one way to keep my burner running using oil quicker than it should. One temp is the send water temp and one is the return water temp right.
I emailed Peerless to ask them and the person who replied said if I had an oil burner with an Aquastat control the high and low had to be 20 degrees difference but the return water had to be at least 150 degree to keep condensation from forming in the flue or someplace.
Does anyone have any knowledge of what it is suppose to be set at. Burner is only about five years old. I just want it to last, to run well and be as economical as possible. Any help will be greatly appreciated.