Grundfos STR2-2.0 CN

The Grundfos STR2-2.0 CN 2 Bar Shower Pump, with its WRAS endorsement, is designed for integration within household plumbing. Its purpose is to amplify water pressure in showers or washbasin faucets, ensuring a more robust and enjoyable flow, especially in rain shower systems. It can achieve a peak pressure of 2 bar.

This pump type is versatile, appropriate for scenarios with either a positive or negative head. In a positive head setting, the water flow is inherently direct. Typically, a cold water reservoir sits above the pump, allowing gravity to facilitate an uninterrupted flow to the pump.

Conversely, a negative head implies that the pump doesn't get its water supply naturally since its source, such as a cold water reservoir, is levelled with or slightly below the outlet of the pump. Here, the pump plays an active role in elevating the water.

Cold water tanks are traditionally housed in a home's loft. The Grundfos STR2-2.0 CN 2 Bar Shower Pump can elevate water to points higher than the cold water tank's altitude, like in loft renovations. A crucial aspect here is ensuring an air-tight pump connection; any air ingress could hamper its pressure delivery capabilities.

Constructed from brass and stainless steel, this pump is optimized for moving tap water without releasing rust particles into the stream. Its twin impeller system enables concurrent hot and cold water transfer. So, one could enjoy a steady shower while someone else uses the sink, without any compromise in water pressure. The pump also incorporates features like anti-vibration and non-slip feet for a quieter operation.

UK regulations strictly prohibit linking pumps to the primary water mains, to prevent potential disruptions in the broader water supply system, which might adversely affect neighbouring households.

How the Grundfos STR2-2.0 CN 2 Bar Shower Pump works:

The pump's activity is responsive to faucet usage. As faucets are opened, causing a pressure decrease, the pump springs into action. It deactivates upon faucet closure and pressure normalization. Water channels from the primary pipeline into a cold water tank with two outlets. One pipe goes to the hot water tank, where the water will be heated before entering the pump. While the other feeds cold water straight to the pump. The pump then amplifies the water's pressure, resulting in a stronger tap output. The image below demonstrates a positive head scenario where water naturally flows to the pump. In instances where outlets align or exceed the cold water tank's height, it represents a negative-head situation.