Pressure switches for water well pumps use a double-spring type switch. One spring is for the cut in pressure and the other is for the cut out pressure. Typical pressure settings for a low-pressure system will be a cut in (start pressure) of 20 PSI and a cut out (stop pressure) of 40 PSI. A higher-pressure system will use a cut in pressure of 30 PSI and a cut out of 50 PSI. When adjusting any pressure switch, you must have a pressure gauge installed on the water system.
Pressure Switch for Water pump Square D (female)
Yee Ken Hardware
Regular price
TT$148.50
Delivering Superior Value.
Safety and Identification of a Square D Pressure Switch
Pull the plastic cover from the pressure switch by removing the single nut on top of the cover. Be aware that there are live electrical parts within easy reach on the pressure switch. Use a wrench that fits the two small nuts on top of the two springs. Typically, one nut size is a 7/16 inch and the other is either a 3/8 inch or ½ inch wrench. The larger of the two springs, called "nut #1," is used for raising and lowering the cut in and cut off pressure. The smaller nut and spring, called "nut #2," is used for widening the gap of the cut off pressures. The smaller spring will raise or lower the gap or pressure difference of the pump turning off. That pressure difference will fall in the range from 1 PSI generally up to 50 PSI. The larger spring raises and lowers the overall pressure of that gap.