There are two kinds of faucets commonly found in the home plumbing system, the compression faucet and the Fuller faucet. The compression faucet is the more widely used, as it stands up better under the high-pressure water system in use today.
The compression faucet controls the flow of water by compressing a fibre washer down onto a valve seat when a threaded spindle is turned. This arrangement enables the compression faucet to control the flow of water easily, even though the pressure of the water is considerable.
The most common reason for a compression faucet's dripping water, after it has been tightly closed, is that the washer inside the faucet has become worn, and no longer fits tightly on top of the valve seat. A package of assorted washers should be kept in the tool kit for just such repairs. In selecting washers, be sure to obtain the kind that can be used on both hot and cold water faucets. These are made of fibre, for a leather washer will not long endure hot water. To replace the washer, close the nearest shut-off valve to the fixture.
If the shut-off valve controlling this particular faucet cannot be located, close the main shut-off valve. Using an adjustable wrench, remove the large packing nut on top of the faucet body under the handle. Place a piece of cloth between the jaws of the wrench and the nut to avoid scarring the finish. After the nut is off the body of the faucet, remove the entire spindle from the faucet by turning the handle counter clockwise. The threaded spindle will unscrew from the faucet and can be lifted out.
The washer is located on the far end of the spindle. Take out the set screw holding the washer with a screwdriver. Often, this set screw is so rusted that it cannot be easily removed. In this case, put a drop of light oil around the screw head and allow a short time for the oil to penetrate. If the screw is badly rusted, replace it with a new one before putting the faucet together.
Select a new washer of the right size and secure it to the spindle with the set screw. Be sure that the set screw is tight. Put the spindle back into the body of the faucet and turn the handle clockwise, as if to close the faucet. Run down the packing nut and tighten it sufficiently to prevent water from coming through the packing inside the cap.
Worn valve seats
Sometimes the cause of a leaky compression faucet is the valve seat inside the faucet. If this valve seat has been, nicked by a worn washer or by the careless dropping of a tool upon it, the washer will not sit tightly and a leak will result. Check valve seats for signs of roughness each time you put on a new washer.
A special valve seat dressing tool can be purchased for filing down the valve seat until it is smooth. After the seat has been smoothed, flush all loose bits of metal out of the faucet before replacing the spindle. If, after dressing down the valve seat and replacing the washer the faucet continues to leak, it can be assumed that the faucet must be replaced.
The packing nut
Another point of leakage is around the stem, when the faucet is open. Such leakage will occur when the packing nut is not tight enough or when the packing or packing washer inside the cap becomes worn. Tighten the nut first, giving it a slight turn and checking to see whether the faucet still turns easily. If this fails to do any good, the packing washer should be replaced. Unscrew the set screw that holds the handle to the spindle and slip the handle off. The packing nut can then be taken off the spindle for repacking.
The Fuller faucet is designed for quick opening and closing and is so constructed that only a small movement of the handle is necessary. The washer used in this faucet is a small ball made of hard rubber or a type of composition. It is attached to the handle of the faucet by means of an eccentric spindle or cam that pulls the rubber ball against the valve seat when the faucet is closed and pushes it away from the valve seat when the handle is in the open position.
Replacing the ball
To repair a leak in a Fuller faucet, you must remove the entire faucet from the pipe so that the ball washer can be taken out. Turn off the water line to the faucet and remove the faucet with a stilson wrench. Once the faucet is off, you can remove the ball valve in the back of the faucet. This ball is held in place by a screw or nut. Move the handle of the faucet to the open position and the ball will be forced to the rear, where it can be easily detached from the rod connecting it to the eccentric spindle.
Obtain a new Fuller ball valve from a hardware or plumbing store, and it is important to get one of good quality and the same size as the old ball valve. After the new ball has been attached to the rod, make sure that the ball is brought against the valve seat when the handle is turned to the closed position. If there is any clearance, it can be taken up by tightening the screw or nut holding the ball to the rod.
A Fuller faucet will leak if the eccentric shaft has become worn and no longer brings the ball valve into the correct position. If this condition exists, the eccentric will have to be replaced.
Shower mixing valves
In many homes equipped with shower baths, separate compression faucets are provided in the shower fixture to control the hot and cold water to the spray. This arrangement is not satisfactory for several reasons. First of all, if the pressure in the cold water line should suddenly drop, the person taking the shower might get scalded. A bad scald can also be due to accidentally turning a faucet in the wrong direction.
There are special shower mixing valves designed to prevent 'any possibility of scalding hot water coming out Of the shower spray. If a shower is not equipped with a safety mixing valve of this type, then special effort should be made to keep the temperature of the hot water in the plumbing system under 140 degrees F.