Safety
Rating for a water heater in a return air plenum
Flame and Smoke
A 50 gallon water heater needs to be heated 50 degrees. How many BTUS are needed?
20,825
What is the constant at which volumetric thermal expansion happens?
.00023
The clear space in front of a heater must be equal to the width of the heater plus___
6 inches
150 PSI
1.61 Gallons
What is a BTU?
British Thermal Unit
How much clear space should be above a heater?
18 inches
Temperature Failure on T&P
210 degrees
How much thermal expansion in PSI would the following create? 140 gallon water heater, 58 degree incoming, 140 degree outgoing?
848.7 PSI
What can 1 BTU do?
Raise 1 lb of water 1 degree
If relief piping is more than 30 feet what must happen?
Shuts off gas and water to a water heater
WAGS Valve
How many BTUS are needed to raise the temperature of a 40 gallon water heater 75 degrees?
24,990 BTU's
What is the layering of water called?
Thermal Stratification
Access to a water heater through a passageway must be a minimum of ___
30 inches
Prevents water from returning into cold water line from water heater
Heat trap
How long would it take to raise the temperature of a 120 gallon water heater with an output of 50,000 BTU's, 65 degrees?
77.9 Minutes
What heat transfer occurs when currents circulate between the warm and cool regions of a fluid?
Convection
Expansion tanks shall be precharged to what?
the static pressure of the system