Which of the following is not an element found in a circulating hot water system?
a) A fire recoil element
b) Air vents
c) Heaters
d) Back flow valves
e) Return Piping
Answer: A
Which of the following is not an element found in a circulating hot water system?
a) A fire recoil element
b) Air vents
c) Heaters
d) Back flow valves
e) Return Piping
Answer: A