Arrived onsite for maintenance for one gas fired boiler. Requested the customer turn on the thermostats up to heat and confirm operation of the boiler and each zone valve. Turned the boiler m and cleaned all burners. Performed a visual inspection of all electrical and inspected all external water components such as the exp tank, fill valve, backflow preventer and the circulator pump. Observed noise from gas valve coil; may be reaching end of functionality but operating now. Also observed noise from Aquastat coil but went away. System heating as it should. Customer had issue with thermostat. Had difficulty setting time and had a flashing clock constantly.. Looking at thermostat and found it was the schedule function that flashing. Set the correct time and recommend using the hold function for that thermostat.
