A hydronic tank holds 120 gallons of water. Using 8.34 pounds per gallon, what water weight should be considered before placing it on a pad?
Correct Answer
C) 1,001 pounds.
Water weight is 120 gallons times 8.34 pounds per gallon, which is about 1,001 pounds.
Why This Is the Correct Answer
Water weight is 120 gallons times 8.34 pounds per gallon, which is about 1,001 pounds.
Why the Other Options Are Wrong
Option A: 834 pounds.
834 pounds. is below the supported result for mechanical water weight calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option B: 920 pounds.
920 pounds. is below the supported result for mechanical water weight calculation; it likely omits allowance, conversion, coverage, or final round-up.
Option D: 1,200 pounds.
1,200 pounds. is above the supported result for mechanical water weight calculation; it likely double-counts allowance, uses the wrong unit, or rounds too early.
Memory Technique
Mechanical Water Weight cart for Checking Equipment: gallons first, times second, whole units last.
Reference Hint
Study anchor (closed-book): memorize Mechanical water weight calculation from 2025 California Mechanical Code and 2025 California Building Code. / Title 24 California Mechanical/Building Code equipment support coordination; know the rule or calculation trigger without relying on exam-room lookup.
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