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Is my "standby" Fuel Oil consumption high ???
Have hour meters on burner and circulator. Finally been warm lately so I can get a handle on standby losses, FHW circulator hasn't run for 3 days. So burner is only supplying standby losses and domestic HW. Tankless DHW coil in furnace water jacket
My hour meter on burner has been averaging 0.9 hour/24 hours. 1.1 GPH nossel, so 1.0 gal/24 hours. Does that sound high?
Only two ~ 10 minutes showers per day, and quick handwashing ( two 60 year olds). Old pre 1.1GPM shower heads, 40 psi water. Without old waterpik shower head attached to shower spout flow is ~ 3 GPM on cold water , less on hot (boiler has 5 GPM orfice) Cold water input is 42 deg F.
60 year old National Sunray IV , boiler # 5-19A/O/OP , rated 128k BTU/hr 1.6 gal/hr
Has original burner, National -US model NB2-K2, firing rate .85-2.0 gal/hr, nozzle = 1.10/ 80 deg/ B
Chimney is ~ 4 stories from cellar floor to top. No motorized damper for when burner is off, has barometric damper.