WM Series

Captive Air and Retention Tanks

Easier to install than steel and tougher over time.

Our WM-Series offers features and benefits steel tanks just can’t match. From their corrosion-proof composite construction... to their lighter weight, easier maintenance and less expensive installation… WM-Series pressure tanks are the preferred choice of professionals.

Features & Benefits

  • Replaceable air cell assures easier field servicing.
  • Greater drawdown than comparably sized steel tanks yields greater efficiency.
  • Extended labor warranty option is available to homeowners.
  • Won’t rust in corrosive environments, particularly important in coastal regions.
  • Quicker and less costly to install, usually requiring only one person and fewer man-hours.
  • Wider pressure setting differential provides greater flexibility.

Find the Right Tank for your Installation

Applications

  • Residential
  • Light commercial
  • Pressure boosting

Specifications

WM Series Quick Connect Performance Data

Model Number Capacity
gal / liter
Maximum
Operating Pressure
psi / kPa / Bar
Drawdown
30/50 Setting**
gal / liter
Diameter*
inch
/ cm
Overall Height*
inch / cm
Height* inlet/
outlet to floor
inch
/ cm
System
Connection
Assembly Weight*
lb / kg
Pallet
QTY.
WM-4 / WM0060 QC 14.5 / 55 125 / 862 / 8.6 4.5 / 17.0 16 / 41 27.5 / 70 1 3/4 / 4.4 1" male NPT 16.9 / 7.6 9
WM-6 / WM0075 QC 19.8 / 75 125 / 862 / 8.6 6.1 / 34.4 16 / 41 32.5 / 82.5 1 3/4 / 4.4 1" male NPT 20.85 / 9.5 9
WM-9 / WM0120 QC 29.5 / 112 125 / 862 / 8.6 9.1 / 34.4 16 / 41 44.5 / 113 1 3/4 / 4.4 1" male NPT 28.80 /13.0 9
WM-12 / WM0150 QC 40.3 / 153 125 / 862 / 8.6 12.5 / 47.3 16 / 41 57.6 / 146.3 1 3/4 / 4.4 1" male NPT 35.05 /15.9 9
WM-23 / WM0300 QC 79.6 / 301 125 / 862 / 8.6 24.6 / 93.1 21 / 53 62.8 / 159.5 2 1/4 / 5.7 1 1/4" male NPT 71.07 / 32.3 4
WM-14WB / WM0180 QC 47.1 / 178 125 / 862 / 8.6 14.6 / 55.3 21 / 53 42 / 106.7 2 1/4 / 5.7 1 1/4" male NPT 46.27 / 21.0 4
WM-20WB / WM0235 QC 60.0 / 227 125 / 862 / 8.6 18.5 / 70.0 24 / 61 42.3 / 107.3 2 1/4 / 5.7 1 1/4" male NPT 52.87 / 24.0 4
WM-25WB / WM0330 QC 86.7 / 328 125 / 862 / 8.6 26.8 / 101.5 24 / 61 56 / 142.3 2 1/4 / 5.7 1 1/4" male NPT 77.22 / 35.0 4
WM-35WB / WM0450 QC 119.7 / 453 125 / 862 / 8.6 37.0 / 140.1 24 / 61 75 / 190 2 1/4 / 5.7 1 1/4" male NPT 102 / 46.4 N/A

WM Series Classic Performance Data

Model Number Capacity
gal / liter
Maximum
Operating Pressure
psi / kPa / Bar
Drawdown
30/50 Setting**
gal / liter
Diameter*
inch
/ cm
Overall Height*
inch / cm
Height* inlet/
outlet to floor
inch
/ cm
System
Connection
Assembly Weight*
lb / kg
Pallet
QTY.
WM-4 / WM0060 C 14.5 / 55 125 / 862 / 8.6 4.5 / 17.0 16 / 41 26 / 66 1 3/4 / 4.4 1" male NPT 14.5 / 6.6 9
WM-6 / WM0075 C 19.8 / 75 125 / 862 / 8.6 6.1 / 34.4 16 / 41 32 / 81 1 3/4 / 4.4 1" male NPT 17.75 / 8.1 9
WM-9 / WM0120 C 29.5 / 112 125 / 862 / 8.6 9.1 / 34.4 16 / 41 44 / 112 1 3/4 / 4.4 1" male NPT 24.75 /11.2 9
WM-12 / WM0150 C 40.3 / 153 125 / 862 / 8.6 12.5 / 47.3 21 / 53 62 / 157 1 3/4 / 4.4 1" male NPT 65.7 /29.8 9
WM-23 / WM0300 C 79.6 / 301 125 / 862 / 8.6 24.6 / 93.1 21 / 53 41.25 / 105 2 1/4 / 5.7 1 1/4" male NPT 43 / 19.5 4
WM-14WB / WM0180 C 47.1 / 178 125 / 862 / 8.6 14.6 / 55.3 24 / 61 41.5 / 105 2 1/4 / 5.7 1 1/4" male NPT 50 / 22.7 4
WM-20WB / WM0235 C 60.0 / 227 125 / 862 / 8.6 18.5 / 70.0 24 / 61 55 1/4 / 140 2 1/4 / 5.7 1 1/4" male NPT 72.75 / 33.0 4
WM-25WB / WM0330 C 86.7 / 328 125 / 862 / 8.6 26.8 / 101.5 24 / 61 55 1/4 / 140 2 1/4 / 5.7 1 1/4" male NPT 72.75 / 33.0 4
WM-35WB / WM0450 C 119.7 / 453 125 / 862 / 8.6 37.0 / 140.1 24 / 61 74 1/4 / 189 2 1/4 / 5.7 1 1/4" male NPT 102 / 46.4 N/A

Note: Maximum external operating temperature 120°F (49°C). Maximum internal operating temperature 100°F (38°C). Minimum operating temperature 40°F (4°C).

* Diameter, height and weight may vary slightly without notice.

** In keeping with current industry standards, drawdown factors are based on Boyle's law. Actual drawdowns will vary depending upon system variables, including the accuracy and operation of the pressure switch and gauge and operating temperature of the system.