If you were anything like me, you would spend hours trying to figure out how certain appliances work when you were a kid. This was especially true for the then-revolutionary sensor-based gadgets that started to appear in the 80s and 90s.
So, if you are still curious about how sensor flush valves, keep reading as I´m about to dispel the secret behind these remotely activated contraptions.
Sensor flush valves are not so different from your regular commercial flushometer. Actually, the configuration and function of internal components are similar to that of regular hand-operated flushometers but without the handle and the inner leverage mechanism. This results in a slimmer design and fewer moving parts that can get damaged due to wear and outright abuse.
So, you still have the two chambers that fill up with water. An upper chamber that holds the seat valve in place thanks to the water pressure. A lower chamber is connected directly to the water supply and is connected to the upper chamber via a small bypass hole. Your regular flush valve will be activated through the handle which will raise the seat valve, liberating the water stored in the upper chamber and sending it down the pipeline into the bowl.
To do away with the handle, designers needed to replace the mechanism that controls the valve seat. However, an automated system that pushes the valve seat up would require too much strength to raise it. So, instead, a solenoid is placed on top of the upper water chamber. Upon receiving a signal, the solenoid releases water, decreasing the pressure on the top chamber and letting water from the lower chamber lift the diaphragm for a full flush. The solenoid is timed, so it will only let a certain amount of water through the valve before getting closed, allowing the upper chamber to get filled again and accumulate enough pressure to close the valve in place.
The necessary signal comes from an infrared sensor located at the front of your flush valve. There is an emitter that, you guessed it, emits infrared light. If this light is reflected back into the sensor, say by a user, it picks the signal up and activates the solenoid.
As you would have guessed, if the solenoid is activated the second the sensor detects a user, the flush will come too early. Sensors are equipped with small microchips that set the rules of the sensor flush valve. Usually, the operator has a set of options. For instance, you can configure your sensor to enter standby mode when it detects a user and releases the water when the infrared signal stops being reflected.
Modern sensors also have safety features that prevent the flush valve from being activated accidentally.
The goal of having a sensor flush valve is to prevent germ transmission and protect your bathroom fixtures from wear. If the need for physical contact is reduced, users won´t need to pull or push any component too hard. This makes them ideal for venues that care about keeping their sanitary installations clean and tidy without having to spend more on additional maintenance. Sensors are usually battery operated, but they are extremely energy efficient, which means that they can perform thousands of flushes per charge.
The best sensor flush valve hardware today is made by brands like Sloan, American Standard, Kohler, Moen, Zurn, and Delta. Their products are extremely high quality, and you can easily find them at Quality Plumbing Supply. They carry the best commercial plumbing brands in the market and supply businesses and contractors with plumbing repair parts and kits. Visit their website today for additional information.