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Step 1: Open the newsletter.
Step 2: Scroll to “What Is the Correct Answer?”
Step 3: Click it.
Looks like B from here.
It is a poorly worded question.
Expansion tanks are necessary on water heating systems because water expands as its temperature increases.
Great catch Bert! We don’t need to further the confusion 
Properly worded question as hot water heating (hydronic) systems require an expansion tank.
The answer is B
Hot water expands, is a liquid and boils at 212. Can I choose all 3? 
Hot Water Expands. Henceforth, Expansion tank.
Im with Austin, I really dislike these types of questions.
If you are connectred to the city and have a closed water system, you will need an expansion tank on your water heater.
Most people would agree with you on all three points in general conversation but in this case we are discussing a pressurized, heated system so the variables are specific and the language is important. So I’m going to nit-pick for a moment. I don’t mean to be pedantic, but it is a science question, so I’m going there. I’ll address all three of these points.
dV = V 0 β (t 1 - t 0 ) (2)
where
dV = V 1 - V 0 = change in volume (m 3 , ft 3 )
β = volumetric temperature expansion coefficient (m 3 /m 3 o C, ft 3 /ft 3 o F)
t 1 = final temperature ( o C, o F)
t 0 = initial temperature ( o C, o F)
Water can be liquid solid or gas depending on temperature. It exists in all three states in your home.
In a water heater tank, water does not boil at 212°F. Pressure affects the boiling temperature. In you water heater, if pressure is at 75 psi then the boiling point is actually 308°F. THis is an important concept because pressurized water can be well below the boiling point in the tank, but as soon as the tpr releases, that water will enter the air outside the tank and can flash to steam. this can be dangerous for someone near the tpr valve.
Expansion tanks are necessary on water heating systems because water expands as its temperature increases.
I was making a joke, but I appreciate the science to learn! Thanks Bert! I guess that’s what happens with ambiguous questions.
I don’t remember who posted this one originally, but it cracks me up every time.
