Customer called for winter preventative maintenance. Service technician checked boiler operation, oiled circulation pump, cleaned burners and cleaned thermocouple. Water shut off valve is dripping and needs to be replaced. The dripping has caused damage and rust to outside cover of boiler. I recommend replacing expansion tank with a bladder type tank. Also discovered that aquastat not shutting off boiler at set temp. Aquastat gauge needs to be replaced. Aquastat not working can cause relief valve to open due to boiler not shutting off. Recommend replacing boiler at some point due age. Customer will make decision on replacement and will highly recommend Advanced Heating & Cooling to all of her friends.