The Grundfos CMB 3-37 is a fixed-speed multistage booster for household water supply, rainwater use and garden irrigation.
rated duty 51.7LPM at 27.7m head.
The pump inlet is a 1" BSP female thread.
The system outlet through the controller is a 1" BSP male thread.
The controller starts the pump when water use causes pressure to fall below its fixed starting threshold, and stops it when water use ends. The starting threshold cannot be adjusted on the controller. Pressure while the pump runs depends on water flow, inlet pressure and losses through the controller and pipework.
The PM1-15 controller has a fixed 150kPa starting threshold.
Dry-running protection stops the pump if the controller detects a lack of water. Anti-cycling protection detects repeated starts caused by small leaks and stops the pump with an alarm. Correct the cause and restore the water supply before resetting the controller, as described in the manual.
Rated duty pairs show flow at the stated head; they are not maximum-flow ratings.
Flow decreases as head increases. Choose the pump for the required flow and pressure at the point of use.
Use clean, thin, non-aggressive and non-explosive water without solid particles or fibres, at temperatures from 0°C to 40°C.
These pumps are not self-priming. Fill the pump casing and inlet pipe with clean water before starting, following the installation instructions. Install on a firm, level base in a ventilated position protected from direct sun, rain and frost.
The pump has a cast iron housing, 304 stainless steel impellers and an AVBE shaft seal with EPDM rubber components. The controller includes a non-return valve. The single-phase motor has built-in overload protection.
Two-year Grundfos Australian consumer warranty from purchase, subject to its terms.