Pressure and a Properly Flushing Toilet

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities, and you.

Pressure and a Properly Flushing Toilet

Replacing a toilet fill valve can solve some of the common toilet problems including excessive noise. With the proper adjustments, an adjustable universal fill valve works on a variety of toilet models. For example, one manufacturer’s fill valve has a gross height adjustment that extends the unit from 9 to 14 inches and a fine water level adjusting screw to set the level of water in the tank. While adjusting the water level lower to be more conservative and save water for each flush may seem like a good idea, the difference in as little as ½ to 1-inch of water height in the tank can mean the difference between the toilet flushing properly or requiring a second flush.

A ½-inch of water is only 0.018 psi, 124.5 Pa or 0.0368 millimeter of mercury (mm Hg). Measuring this low pressure is often a problem for pressure sensors but the All Sensors MLDX Series has 5 and 10 inH2O ratings to measure the low pressures found in many medical and heating, ventilation, and air conditioning (HVAC) flow applications, as well as other ratings up to 100 psi. Fortunately, for toilet adjustments, it is simply a matter of observing the situation to make the proper adjustments and no pressure sensing is involved.

Fluidmaster Toilet Fill Valve

Image courtesy of Fluidmaster

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