Quick answer: Choosing a Grundfos home booster pump comes down to three things: how many bathrooms you have, what kind of showers you use, and how water reaches the pump. Find your bathroom count in the tables below, then ask our team to confirm the model.
You know the feeling. You're mid-shower, nicely warm, and someone downstairs turns on the kitchen tap. Your shower drops to a dribble. 😤
Or you've just moved into a double-storey home and the upstairs bathroom barely has enough pressure to rinse out shampoo. The fix is usually a water booster pump. The problem is the wall of model numbers (CMB 3-37, CMBE 5-62, SCALA1 3-45) that tell you nothing about which one fits your house. This guide covers the popular Grundfos CMB, CMBE and SCALA ranges and gives you a simple table for each.
You probably need a home water booster pump if you notice any of these:
- Weak shower pressure upstairs
- Pressure drops when two bathrooms are used at the same time
- Your rain shower feels weak or drizzly
- Taps lose pressure when the washing machine or another tap is running
CMB, CMBE or SCALA? The Short Version
- CMB is the compact, popular Grundfos home booster. You choose between a PM1 version (built-in pressure control) and a PT version (pump with a pressure tank). Browse the Grundfos CMB range.
- CMBE is the variable-speed booster. Its integrated speed control keeps pressure more consistent as demand changes, so your shower stays steadier when another tap opens. Browse the Grundfos CMBE range.
- SCALA is the all-in-one, self-priming booster. SCALA1 adds Bluetooth connectivity through the Grundfos GO app, and SCALA2 has intelligent pump control. Browse the Grundfos SCALA range.
How to Read the Selection Tables
- Water heater. Grundfos Malaysia's figures are for homes with a solar or electric storage water heater. With an instant electric water heater, Grundfos lists the same counts as normal showers for every model in these tables.
- Shower type. 🛁 Normal shower and 🚿 Rain shower have separate counts, and rain showers list fewer bathrooms. The leaflets do not say what counts as a rain shower, so check the flow and pressure your shower needs.
- Overlaps. Some models list the same bathroom count. If two models fit, ask us which suits your water source and pipework.
- A guide, not a guarantee. The right model also depends on your water supply, how many taps and showers run at the same time, your piping and the installation. Treat the counts as indicative, not guaranteed performance.
📋 Grundfos CMB: How Many Bathrooms?
Grundfos lists the same bathroom counts for the PM1 and PT versions of each CMB model, so one table covers both. Pick the version you want in the Model column.
| Model | Bathrooms it covers |
|---|---|
|
CMB 3-37 PM1 | PT |
🛁 Normal shower: 1-3 bathrooms 🚿 Rain shower: 1 bathroom |
|
CMB 3-46 PM1 | PT |
🛁 Normal shower: 1-3 bathrooms 🚿 Rain shower: 1-2 bathrooms |
|
CMB 5-37 PM1 | PT |
🛁 Normal shower: 4-5 bathrooms 🚿 Rain shower: 3-4 bathrooms |
|
CMB 5-46 PM1 | PT |
🛁 Normal shower: 6 bathrooms 🚿 Rain shower: 5 bathrooms |
Source: Grundfos Malaysia CMB PM1 and CMB PT product leaflets. Grundfos may have updated its figures since, so please ask our team to confirm them for the model you choose.
Grundfos CMBE: How Many Bathrooms?
The CMBE is Grundfos's variable-speed booster. Its integrated speed controller adjusts the pump to keep a constant pressure in your pipes, so pressure stays more consistent when several taps open and close. Grundfos also lists one-touch pressure adjustment and dry-run protection with auto-restart. On our product pages the three models appear as CMBE362, CMBE562 and CMBE1054.
| Model | Bathrooms it covers |
|---|---|
| CMBE 3-62 | 🛁 Normal shower: 1-3 bathrooms 🚿 Rain shower: 1-2 bathrooms |
| CMBE 5-62 | 🛁 Normal shower: 4-6 bathrooms 🚿 Rain shower: 3-5 bathrooms |
| CMBE 10-54 | 🛁 Normal shower: 7-11 bathrooms 🚿 Rain shower: 6-10 bathrooms |
Source: Grundfos Malaysia CMBE product leaflet. Please ask our team to confirm the current figures for the model you choose.
Grundfos SCALA1 and SCALA2
SCALA1 is an all-in-one, self-priming booster with built-in Bluetooth connectivity. With the Grundfos GO app on your phone you can set it up, control it and troubleshoot it. We list the two SCALA1 models below.
| Model | Bathrooms it covers |
|---|---|
| SCALA1 3-45 | 🛁 Normal shower: 1-3 bathrooms 🚿 Rain shower: 1-2 bathrooms |
| SCALA1 5-55 | 🛁 Normal shower: 4-6 bathrooms 🚿 Rain shower: 3-5 bathrooms |
Source: Grundfos Malaysia SCALA1 product leaflet. Please ask our team to confirm the current figures for the model you choose.
What About SCALA2?
The Grundfos SCALA2 is an all-in-one, self-priming booster pump with intelligent pump control that adjusts its operation to help maintain comfortable water pressure as household demand changes. Pump, motor, tank, sensor, drive and non-return valve sit in one compact unit, with dry-running protection and an outdoor-ready design. Grundfos designs it for residential buildings with up to three floors and eight taps. Grundfos does not publish a bathroom count for the SCALA2, so we do not give a Grundfos figure. Any bathroom guidance on our product page is CT Hardware's own indicative estimate, not a Grundfos rating, so please ask our team to confirm it for your home. See the full Grundfos SCALA collection.
PM1 or PT? How CMB Boosters Control Pressure
- PM1 has built-in pressure control. It starts and stops the pump automatically when you open or close a tap and protects the pump from dry running. Grundfos describes it as compact, quiet and maintenance free.
- PT is the pump with a pneumatic pressure tank (18 L on the models we list). Grundfos says the tank smooths the flow from your taps and cuts down how often the pump starts and stops. The tank makes the unit taller, so check the space where it will go.
The bathroom counts are the same for both versions. Choose PM1 if you want the more compact unit, or PT if you prefer a tank to buffer the flow. For steadier pressure that adjusts to demand, look at the CMBE.
PM1 models: CMB3-37 PM1 | CMB3-46 PM1 | CMB5-37 PM1 | CMB5-46 PM1
PT models: CMB3-37 PT | CMB3-46 PT | CMB5-37 PT | CMB5-46 PT
Water Supply and Installation
💧 Check Your Water Supply
Grundfos CMB booster pumps need enough water flowing into them to work properly. They are commonly installed with a water tank positioned above the pump, allowing water to flow into it naturally.
These standard CMB pumps should not be expected to pull water up from a tank below them. If you're unsure, ask a qualified installer to check your water supply and recommend the right setup.
Other Things to Check
- Simultaneous use. Count the showers, taps and appliances that may run at the same time, for example two showers and a washing machine. If many people use water together, ask us to review your choice.
- Pressure you want. Decide the pressure you want at the highest tap, and check the minimum pressure and flow your shower or fitting needs.
- Piping. Check the age and condition of your pipes and any history of leaks. Ask a qualified plumber to check the pipework before you add a booster pump.
CT Hardware does not provide pump installation or on-site assessments. We can guide you on choosing the model and, where appropriate, refer you to independent installers.
SIRIM Certification and CT Hardware Support
Grundfos CMB, CMBE and SCALA booster pump ranges are SIRIM certified.
CT Hardware Sdn Bhd is an authorized Grundfos dealer, listed in Grundfos Malaysia's Domestic Building Services (DBS) professional dealer directory. We regularly stock selected Grundfos CMB, CMBE and SCALA home booster pumps, subject to actual availability. Stock can differ by branch, so check the product page or ask before you visit. Other Grundfos models may be available to order.
Warranty terms depend on the pump model; see our Grundfos warranty information.
Still not sure? WhatsApp our team with your number of bathrooms, your shower type and how water reaches the pump.
🛒 Shop Grundfos Boosters at CT Hardware
- All Grundfos booster pumps
- The Grundfos CMB range (PM1 and PT)
- The Grundfos CMBE range (variable speed)
- The Grundfos SCALA range (SCALA1 and SCALA2)
- More water pumps and water pump accessories
❓ Frequently Asked Questions
How many bathrooms can a Grundfos booster pump serve?
Check the CMB, CMBE and SCALA1 tables above. The count depends on the model and your shower type, and it is indicative, not guaranteed performance.
Which Grundfos range should I choose: CMB, CMBE or SCALA?
Start with your bathroom count in the tables. Choose CMBE for pressure that adjusts to demand, SCALA for a compact all-in-one self-priming unit, and CMB for the popular PM1 or PT booster. Ask us if two options fit.
Do I need a different pump if I have a rain shower?
Use the 🚿 line of the table. It lists fewer bathrooms per model than the 🛁 line. Check your shower maker's flow and pressure figures, and ask us to compare the options.
What is the difference between PM1 and PT models?
A PM1 model has built-in pressure control. A PT model combines the pump with a pressure tank. The bathroom counts are the same, so the choice is about the type of unit you prefer.
Can a Grundfos CMB pump pull water from a tank below it?
Standard CMB pumps should not be expected to. They need enough water flowing in, commonly from a tank above the pump. Ask a qualified installer to check your setup. SCALA pumps are self-priming, so ask us if your water source is below the pump.
Can I install a Grundfos booster pump myself?
We recommend a qualified plumber or installer. CT Hardware does not provide pump installation or on-site assessments. Correct pipe sizing and placement make a big difference to performance.
Does CT Hardware keep Grundfos booster pumps in stock?
CT Hardware regularly stocks selected Grundfos CMB, CMBE and SCALA home booster pumps, subject to actual availability. Stock can differ by branch, so check the product page or ask before you visit.
How much is a Grundfos booster pump in Malaysia?
Prices depend on the model. Check the latest price and promotions on our Grundfos booster pump collection, or WhatsApp our team for a quote.
Written by the CT Hardware water pump team. Last updated: October 2026.