Bristan Shower Cartridge Problems

Owners of Bristan Prism Thermostatic showers have encountered a recurring problem where the water runs cold even when other taps in the house provide hot water. In many cases, the cartridges need frequent replacements. Notably, the issue seems to arise irrespective of limescale build-up, as many users have reported no visible limescale on the cartridge even when the problem occurs.

Possible Causes:

1. Unequal Pressure: Showers typically work on a pressure ratio. If the pressure is not balanced correctly, it can lead to temperature inconsistencies.
2. Cartridge Wear and Tear: The moving end of the cartridge can stick hard against the main body of the cartridge. When this happens, it affects the water temperature, turning the hot water cold.
3. Temperature of the Hot Water Supply: Overly hot water might trigger a failsafe mechanism in the shower, causing it to turn warm or cold.
4. Seal Corrosion: Corroded seals could allow too much cold water into the mixer, resulting in a colder shower.
5. User Behavior: Over-rotating the shower knob might affect the shower’s functionality. Some users have reported a peculiar off position of the shower knob that tends to confuse them, leading to inadvertent over-rotation.

Solutions:

1. Regular Cartridge Maintenance: One of the consistent observations from users was the sticking of the moving end of the cartridge. It’s essential to ensure regular maintenance to prevent this from occurring. Keeping it free and checking for any physical blockages can significantly improve its lifespan.
2. Upgraded Cartridges: Bristan offers updated plastic cartridges which are reportedly better in combating these issues. They are less susceptible to limescale buildup, and the silicone grease used in them lasts longer, preventing jamming.
3. Pressure Balancing: Ensure that the shower operates at equal pressures. Unequal pressure can cause strain on the cartridge and affect water temperature. Checking the pressure and making the necessary adjustments can help resolve the issue.
4. Temperature Monitoring: For those with exceptionally hot water, it might be worth monitoring and adjusting the water heater’s temperature. This might prevent any potential failsafe mechanisms from being triggered.
5. Seeking Professional Assistance: While DIY solutions are often sought after, consulting with Bristan’s technical department or a professional plumber can provide more in-depth solutions specific to the model of the shower owned.

Conclusion:

Bristan Prism Thermostatic shower users have faced issues with the cartridge leading to unexpected cold showers. While there are several potential causes for this, there are also a variety of solutions. Regular maintenance, pressure adjustments, and considering upgraded cartridges are among the steps that can be taken to ensure a consistent and warm showering experience. If all else fails, seeking professional assistance might be the best course of action.