View Single Post
  #26   Report Post  
Posted to alt.home.repair,misc.consumers.frugal-living,sci.electronics.repair
James Sweet James Sweet is offline
external usenet poster
 
Posts: 1,572
Default Quick basic advice on a dripping gas 40-gal hot-water heater


I agree that the rated fuel consumption for motor vehicles is off - I
haven't averaged that low for at least 15 years. For instance, my car is
rated 20/29 for city/highway - last week I averaged 33.2 mpg in about 440
miles of mixed driving according to the car's odometer and the reading on
the pump when I gassed up on Friday evening. According the average
mileage
display on the dashboard of the car, I got 34.1 mpg, and I suppose the
difference could be due to the attendant (no self service gas in NJ)
filling
the tank right up to the gas cap and/or inaccuracies in the pump or
odometer, or even simply to the fact that I fill up the tank at the end of
the day (when the car and the gas is at its warmest) but do about half my
driving in the morning (when the gas is the coolest). Which means simply
that a full measured gallon on a Friday afternoon is probably less than a
gallon on Monday morning simply due to the expansion and contraction that
go
with changes in temperature.



The expansion and contraction based on temperature for a volume as small as
a tank of fuel in a car are so tiny that you'd never be able to measure them
with anything around the house, and certainly not the odometer in your car.
The fuel temperature varies over a range of perhaps 60F max, usually much
less.