Completed annual maintenance on one oil fired boiler, changed filter, nozzle, and strainer, vacuumed combustion chamber and flu pipe, inspected all water components, did notice boiler pressure was at 20 while running which is a little high gave customer estimate for expansion tank, also customer stated every once in awhile boiler will short cycle when there is a call for hot water, cycled boiler multiple times could not get it to recreate itself, the zone valve for hot water heater hasn’t been changed in awhile could be taking awhile for valve to make contact to switch gave customer estimate for zone valve as well. Combustion tested normal, no leaks, system operational and working.