An unloader valve works by diverting water flow into a bypass as soon as a trigger gun valve is closed. These two valves work together to create a unique system that directs water into a float tank or a pump inlet. Unloader valves are used to circulate water into the inlet side of a pump, while trigger gun valves control the flow of water.Know More
There are two types of unloader valves: the pressure-actuated unloader and the flow-actuated unloader. The pressure-actuated unloader works by responding to increases and decreases in water pressure. The flow-actuated unloader relies completely on water flow; a halt in water flow increases the internal pressure.
Most unloaders are designed to function with 5 to 10 percent of water flow in the bypass at all times. This is true for all pressure-actuated unloaders. These types of unloaders usually need at least 10 percent of water capacity in the bypass. The water in the bypass provides a type of cushion between the valve ball and the seat to help lessen the impact of two metals being forced together during normal valve operations.
No machine that uses unloaders should run in a bypass mode continuously. This is because the closed loop rapidly increases the temperature of the water. Most water pumps are not designed to handle water that gets hotter than 140 degrees Fahrenheit.Learn more about Plumbing
A thermal expansion valve in refrigeration or air conditioning systems uses a temperature sensing bulb to open a valve, allowing liquefied refrigerant to move from the high pressure side of the system to the low pressure side before entering the evaporator. As the evaporator temperature decreases, pressure on the bulb decreases, allowing a spring to close the valve, according to Reference.com.Full Answer >
Foot valves work by ensuring that the water in a well pump only flows in one direction. Foot valves are a type of check valve, but they differ in that the flow area is larger in size than the rest of the pipe. This limits the amount of head loss in the pumping system.Full Answer >
According to PlumbingMart, water hammer can be eliminated by reducing water flow to appliances or installing AA-sized water hammer arresters on faucets and appliances. Water cushions can also be used as a temporary fix to eliminate water hammer.Full Answer >
Overflowing toilets are most often caused by blockages or defects in the plumbing or the tank float mechanism that regulates water flow. Water builds up inside the toilet, but because there is a blockage where the water usually escapes, the water level increases to the point of overflowing.Full Answer >