Bosch dishwashers and washing machines are known for their reliability and efficiency, but even top-quality appliances can encounter problems. One common issue users face is when the appliance does not draw water despite having sufficient water pressure from the tap. This situation can be frustrating, especially when you’re unsure what’s causing the problem. In many cases, the issue lies with a malfunctioning flow sensor or a blocked electric valve due to lime scale.

Let’s explore how these components work, why they fail, and what you can do about it.

Understanding the Basics: Water Supply and Internal Components

When a Bosch appliance starts a wash cycle, it opens the electric inlet valve to allow water to flow in. The flow sensor monitors how much water enters the machine and signals the control board to stop the water flow once the required amount has been reached.

If your Bosch machine doesn’t fill with water, even though the tap is fully open and water pressure is strong, then the problem is likely inside the machine. Two common culprits are:

1. Flow Sensor Malfunction 
2. Electric Valve Blockage Due to Lime Scale 

1. Flow Sensor Malfunction

The flow sensor is a precision part that monitors the volume of water entering the appliance. It ensures that the machine receives just the right amount—no more, no less. When the flow sensor malfunctions, it may send incorrect signals to the control unit, causing the appliance to shut off water flow prematurely—or not initiate it at all.

Signs of a faulty flow sensor include:

• No water entering the machine despite the tap being on. 
• The appliance stopping mid-cycle with an error code. 
• Long or incomplete wash cycles. 

Causes of failure:

• Wear and tear over time. 
• Accumulation of debris or lime inside the sensor. 
• Electrical connection issues or sensor damage. 

In some cases, the sensor can be cleaned and reused. However, if the sensor is damaged, replacement is the only option.

2. Electric Valve Blockage Due to Lime

Lime scale is the enemy of any water-fed appliance. If your home has hard water, lime deposits can gradually build up inside the electric inlet valve, eventually leading to partial or complete blockages. When this happens, the valve cannot open or close properly, even if the control board is functioning normally.

Common symptoms of a blocked valve include:

• No water flow into the appliance. 
• Audible clicking without water entry. 
• Error messages related to water intake. 
• Noticeable lime deposits around valve connectors. 

The valve may be blocked internally or externally. Disassembling and cleaning may help, but heavy lime build-up usually requires full valve replacement.

Diagnosis and Repair: Leave It to the Experts

Diagnosing whether the issue is the flow sensor or the electric valve requires technical expertise. Modern Bosch appliances often display error codes, but these codes can point to multiple components. A professional appliance repair technician will:

• Inspect water pressure and inlet filters. 
• Test the inlet valve and its electrical signal. 
• Examine the flow sensor and perform continuity tests. 
• Identify and remove lime scale, if present. 
• Replace faulty components with OEM Bosch parts. 

Attempting a DIY repair without proper knowledge could lead to further damage, increased costs, or safety risks. It’s always safer and more efficient to trust a certified technician.

Preventive Measures for the Future

To minimize the risk of flow sensor or valve failure, especially due to lime scale, here are some tips:

• Use a water softener if your water supply is hard. 
• Periodically run an empty cycle with a descaling agent. 
• Clean filters and inlet screens every few months. 
• Schedule professional maintenance annually. 

By being proactive, you can extend the lifespan of your Bosch appliance and avoid unexpected breakdowns.

Need Help? Call Chula Vista Appliance Repair Company

If your Bosch appliance isn’t drawing water and you suspect a flow sensor malfunction or a blocked electric valve, don’t wait for the issue to worsen. Chula Vista Appliance Repair Company offers expert diagnostics, fast repairs, and genuine Bosch parts for long-term reliability.

Contact us today to schedule your service. We’ll get your appliance back to working order—quickly and professionally.

Contact us

(619) 880-5508