I recently purchased a new home which uses an oil fired burner for heat and hot water. Connected to the burner is a Honeywell Triple Aquastat control L8124A. There are three dials: Hi which is set to 200 dg, low which is set to 180 dg and the differential which is set to about 17. Does anyone know what these mean and whether they are set properly? I want the burner to run efficiently but I think these settings are high. Thanks for your help.