Estate for years. An estate for years is one which is to continue for a definite period fixed in advance by. agreement between landlord and tenant. The name is somewhat misleading because the period may be for less. than a year, measured in specific days, weeks, or months. Estate from period to period. An estate from period to period (or periodic tenancy) is one which continues for. periods of time (typically year-to-year, month-to-month, or week-to-week) as designated by landlord and tenant. in their agreement. The most common periodic tenancy is the month-to-month tenancy.
You will still require 8.34 BTU to raise the temperature of a gallon of water one degree F. 1  I say approximately because the weight of water varies slightly with its temperature. 2  Water is at its densest at 4 degrees Celsius (39 degrees F). 3  A gallon of water at temperatures above and below that value will weigh less.
At 62 degrees Fahrenheit, one gallon of water weighs 8.338 pounds. At this temperature, a 40-gallon water heater would have 333.52 pounds of water. If the water heater used 40,000 BTUs per hour, it would take approximately a half of one minute to raise the temperature in the tank one degree. If the thermostat is set to 122 degrees Fahrenheit, it would take approximately 30 minutes to heat the tank if all heat is transferred to the water.