The burner has a temperature control to keep it's water chamber within a certain range. It will run to satisfy that, but should not run often. You can turn the burner off for the summer without any harmful consequences. If your air conditioning is running so cold that it is overriding the thermostat setting for the heat, then I would raise the A/C temp. for sure!My oil burner is always turning on, even in summer. How can I stop that (I have a gas water heater).?
There should be a swich on the furnace turn it off also check the wall thermostat and make sure the temp . is at the lowest possible setting .If you have your a/c on this will make the furnace kick on ,been there done that!