The Grundfos 0.9HP Booster Pump (CM 5-4) with a 24-litre storage tank is a single-phase pressure pump that delivers constant water pressure to homes with 2 to 4 bathrooms and up to 2 rain showers. It runs at 0.7kW on 230V, handles up to 10 bar, and comes with a 1-year warranty.
What it does, and when you need it. If your shower goes weak when someone opens a tap elsewhere, or your rain shower dribbles instead of pouring, your water pressure is the problem. A booster pump fixes it. This unit maintains constant pressure automatically: when pressure drops to a pre-set level, the pump starts; when water use stops and pressure rises to the stop point, it switches off. You get consistent flow at every outlet without thinking about it. For a home with a rain shower which needs real pressure to work as intended a booster pump is often the difference between the shower you paid for and a disappointment.
Built by Grundfos, and the specs that matter. Grundfos is the reference name in pumps, and the CM 5-4 reflects it: silent operation, a compact design, built-in thermal protection, and F-class insulation. It handles up to 80 start/stop cycles per hour, so it copes with a busy household's on-off water use without strain. The 24-litre pressure tank smooths delivery and reduces how often the pump cycles, which extends its life. Maximum pressure is 10 bar, operating pressure 6 bar, with 25 x 32 mm inlet/outlet and a liquid temperature range of 20°C to 120°C.
