In your home, at the kitchen sink, the problem that is of most concern is some kind of leak. If a leak is discovered in the cabinet beneath the kitchen sink, it is in your best interest not to ignore it or defer the maintenance, but, to evaluate the situation at your earliest convenience. To ignore the situation is to invite worse problems down the road. If left unchecked, in the short term, it could result in the growth of mold and mildew. Physical damage to the cabinetry is what follows, as well as to the flooring and to whatever is directly below in the basement. Deferred home maintenance is always more involved -which translates to more costly.
Remove everything from the cabinet under the sink and, with a good source of light, examine the sink drain to determine if it is leaking. If it is not, examine the water supply shut-off valves behind the drain. Examine the underside of the faucet assembly to determine if it is leaking. That would include the hose sprayer connection on the underside of the faucet.
It is a good idea to get in the habit of consciously looking for evidence of moisture under the sink whenever you reach into the cabinet to retrieve something stored there. Early detection is preferable.
After a leak has been discovered and remedied, always attempt to dry out cabinet areas using fans, if possible, to expedite the process. If you can prevent the growth of mold and mildew you will be better off.
Often a worn faucet valve assembly (or faucet cartridge) will allow water leakage which will be evident on the top side of the faucet assembly. A replacement parts kit is usually available for your make / model of leaky faucet. Before disassembling the faucet, shut off both the hot and cold water isolating valves located under the sink. If there are no isolating valves, locate the supply valves in the basement. It may be necessary to close the main supply valve if no isolating valves are present.
Open the faucet to relieve and residual pressure in the lines. To begin replacement of the single handle faucet valve, remove the ‘allen head’ set-screw and pull of the handle. Pull off the shroud and unscrew the threaded retaining collar, etc., and the ‘horseshoe’ spring clip that retains the valve.
Pay close attention to the parts and the order in which they are removed for later re-assembly.
Insert the new valve and replace the parts in the order in which they were removed. The valve must be oriented so when the handle swings right the cold water is tapped and when the handle swings left, the hot water is tapped.
Restore the water supply and check for leaks and the correct hot / cold orientation.
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