Essex, Vermont homeowners replacing standard-efficiency boilers with 96% AFUE condensing units typically see fuel savings of $400–$700 per year based on Vermont average heating oil prices of $3.80–$4.20/gallon. Langlois Plumbing, Heating & AC LLC installs high-efficiency boilers in Essex for gas, propane, and oil systems. Most Essex boiler replacements are completed in one day with heat restored before we leave.