If two pumps, identical in all respectes and each capable of delivering a discharge 'Q' against head 'H', are connected:
1
in parallel, the resulting discharge is Q against a head of 2H.
2
in series, the resulting discharge is 2Q against a head of 2H.
3
in series, the resulting discharge is 2Q against a head of H.
4
in parallel, the resulting discharge is 2Q against a head of H.