Product Overview
NOTE: $35 Fixed Shipping Rate not available in Hawaii, Alaska or Puerto Rico.
With a CM Booster Plus 3-4 On Demand Pump, you can expect much higher flows and pressures than that of the popular MQ 3-45 model but with the same on demand functionality. The CM Booster Plus Pumps are made with higher quality components (all stainless steel internal parts) and have a significantly longer life expectancy than that of the MQ 3-45. The CM Booster Plus combines the Grundfos CM 3-4 Pump with the Grundfos PM Plus Pressure Manager, making it a high quality, high performance above ground pump with on demand capabilities.
The Grundfos CM Booster Plus Self-Priming is a compact booster pump designed for domestic and light industrial use. The booster unit consists of a robust multistage centrifugal pump and a generator friendly PM Plus Pressure Manager. The Pressure Manager allows the pump to start and stop automatically according to demand and protects the pump from dry running. The CM Booster is the perfect solution if you are struggling with insufficient mains pressure, and it can also be used with above or below groundwater sources.
Features
- Compact (small footprint)
- Easy installation
- High reliability
- Wide performance range
- Automatic resetting of alarms
- Adjustable start pressure
- Dry-running protection
- Anti cycling (leak detection)
- Max continuous operating time
- Power: 115V (May also be configured for 220V. Select 220V if needed. Note that the 220V option does not come with a plug, only bare leads, 2 hot wires and a ground wire.)
Pump
- Low noise level
- Grundfos motor
Pressure Manager
- User-friendly interface
- Flexible power supply
- Internal pressure membrane
- Power-on indication
- Pump running indication
- Alarm indication
- Dry-running protection
- 1" FNPT outlet connection
- Pressure Gauge
- Integrated Non-Return Valve
Documentation:
CM Brochure
CM Product Guide
CM Installation and Operating Instructions
PM2 Brochure
PM2 Product Guide
PM2 Replacement Chart
Submittal Document
Performance Curve
Compares flow and pressure of the CM Booster Plus to the popular Grundfos MQ 3-45 pump. The CM Booster Plus 3-4 pump offers higher flows and pressures with the same on demand functionality. It will supply 12 GPM (Gallons per minute) @ 65 PSI, 16 GPM @ 57 PSI and 20 GPM @ 46 PSI at the pump's discharge. The CM Booster Plus 3-4 is made with higher quality components (all stainless steel internal parts) and has a significantly longer life expectancy than that of the MQ 3-45.
About the CM 3-4
The Grundfos CM pump has been created with compactness, flexibility and reliability as its central features. This horizontal multi-stage, close-coupled pump is a compact, reliable and quiet pump designed to work in a variety of applications.
CM pumps are fitted with mains-operated motors.
A Grundfos engineered mechanical shaft seal has been designed to eliminate industry-wide problems with shaft seals sticking where SIC-SIC seal faces are used. The solution builds on both the implementation of a rotation stop on the stationary ring and different surface finishing on both the stationary and rotating rings.
Flexibility
The Grundfos CM is designed to be used in a variety of applications, including:
- Washing and cleaning (washing machines)
- Rainwater Harvesting (flooded suction from a water storage tank)
- Temperature control (heating/cooling)
- Building services
- Irrigation
Applications 
- Mains water pressure boosting
- Rainwater supply from above ground water tanks
- Rainwater supply from below ground water tanks
- Rainwater supply from other below ground water sources - dams/rivers etc.
| Feature | CM Booster Self-Priming |
|---|---|
| Pressure Manager Plus (refer to table below | Yes |
| Self-Priming capabilities | Yes |
| Stainless steel wetted components | Yes |
| Feature |
Pressure |
|---|---|
| Power on indication | Yes |
| Pump running indication | Yes |
| Alarm indication | Yes |
| Dry-running protection | Yes |
| Free position in installation | Yes |
| Suitable for generator supply | Yes |
| Rotary outlet connection | Yes |
| Integrated non-return valve | Yes |
| Cycling alarm | Yes |
| Integrated pressure sensor from Grundfos Direct Sensors | Yes |
| Adjustable start pressure | Yes |
| Start/stop with 1 bar differential pressure | Yes |
| Auto restart after dry running | Yes |
| Maximum run time 30 min (safety) | Yes |
| Pressure indication | Yes |
| Internal pressure tank | Yes |
Features and Benefits
Robust design
All wetted parts are made from high quality, corrosion resistant stainless steel to ensure the longest life possible.
User-friendly interface
The pump features a user-friendly interface with LED indicators displaying power status, pump running, alarm indication and pressure indication.
Protective features
The pump incorporates a range of protective features such as; dry run protection, thermal overload protection, cycling alarm and maximum continuous operation time - 30 mins to protect the pump and ensure a long life.
Easy installation
The booster unit is a compact and adaptable solution, which makes it suitable for most installations. Simply connect the inlet and outlet and adjust the start pressure to suit individual requirements and you have a fully operational booster unit.
Integrated non-return valve
Non-return valve for backflow prevention.
About the PM Plus
The PM Plus Pressure Manager is a controller that allows your pump to operate "on demand". On demand essentially means that when there is a drop in pressure in the water line, the PM Plus will send a signal to the pump to turn on and begin pushing water. The pressure drops until it reaches 20 PSI to 32 PSI (1.5 or 2.2 bar), then starts the pump. The pump will continue to run until the demand for water stops. E.g. A valve is closed, and the flow of water ends. At this point, the PM Plus will send a signal to turn off the pump.
The Grundfos PM Plus pressure manager is designed for automatic start/stop control of Grundfos pumps and other water supply pumps. The PM Plus is the all-round control solution offering adjustable start from 0-90 PSI. This enables customization to different types of installations at the desired comfort level. The start pressure is set by means of DIP switches located behind the control panel, whereas the current pressure is indicated on the LED display on the front of the PM Plus. The PM Plus starts the pump when the start pressure is reached, and the pump keeps running as long as there is a flow. The PM Plus can be optimized for operation with an external pressure tank by enabling the 14 PSI differential-pressure function. This function significantly reduces the number of operating hours of the pump in installations with pressure tank.
Furthermore the PM Plus incorporate a number of functions which protect both the pump and the installation.
Protective functions include:
- dry-running protection
- cycling alarm
- maximum continuous operating time (30 minutes)
- auto-reset function which can be used to automatically restart the pump
