Maximum system output with, Minimal pump starts, Effective system protection) – Amtrol Pre-Pressurized Water System Tanks WELL-X-TROL User Manual
Page 4: Choose the amount of protection you need, Esp sizing table

esp
(Effective System Protection):
maximum system output with
minimal pump starts
The ESP sizing procedure covers modern residential water-use habits, increased off-peak
demands and the general increase in water use that have occurred over the past twenty-five years.
ESP sizing is designed to reduce pump wear and tear, and reduce energy consumption by keeping
pump starts to a minimum.
Choose the amount of protection you need.
ESP I:
Tank selection is based on approximately one minute minimum pump running time.
This is recommended for pumps up to 3/4 H.P.
ESP II:
Tank selection is based on approximately two minute minimum pump running time.
This is recommended for 3/4 H.P. or larger pumps.
ESP Sizing Table
OPERATING PRESSURE - PSIG
PUMP DISCHARGE
ESP I
ESP II
RATE GPM (Approx.)
20/40
30/50
40/60
20/40
30/50
40/60
5
WX-202
WX-202
WX-202
WX-202XL
WX-205
WX-205
7
WX-202
WX-202
WX-202XL
WX-205
WX-250
WX-251
10
WX-202XL
WX-205
WX-205
WX-251
WX-251
WX-255
12
WX-205
WX-250
WX-250
WX-251
WX-255
WX-255
15
WX-250
WX-250
WX-251
WX-255
WX-302
WX-350
20
WX-251
WX-251
WX-255
WX-350
WX-350
(2) WX-255
25
WX-251
WX-255
WX-302
(2) WX-251
(2) WX-255
(2) WX-302
30
WX-255
WX-302
WX-350
(2) WX-255
(2) WX-302
(2) WX-350
35
WX-302
WX-350
WX-350
(2) WX-302
(2) WX-350
(2) WX-350
40
WX-350
WX-350
(2) WX-255
(2) WX-350
(2) WX-350
(3) WX-302