Why do boilers have allowances for expansion?
1 To prevent the brickwork from cracking2 To prevent undue stress on the pipework
3 To prevent thermal shock to the steam drum
4 Because the boiler is not always operating at the same temperature
A ) 1, 2, 4
B ) 2, 3, 4
C ) 1, 2
D ) 2, 4
E ) 2, 3
Answer: A