Hard Water
When calcium builds up in or around plumbing fixtures, the source of the buildup is hard water. Hard water does not harm your health but it does lead to the chalky, white, calcium accumulation. If you do not clear up the calcium buildup in plumbing fixtures such as your faucets on a regular basis, the buildup may drop your water pressure or even cut off the flow of water through the fixture.
Aerators
Modern faucets have an aerator at the spout opening. The aerator catches debris such as pipe shavings, pebbles and even calcium deposits before they enter the sink or bathtub. Over time a faucet’s aerator may begin to clog up with the debris, and you must take action to clear it out. You must unscrew the aerator from the spout opening with a pair of pliers. Wrap electrical or duct tape around the pliers’ jaws so they do not scratch the finish on the aerator. With the aerator removed, you must take it apart and rinse it with clean water. If the calcium deposits are hardened on the aerator, you must soak it in vinegar.
Faucet Clearing
If the aerator is clear and the faucet still does not work properly, you must check for calcium buildup elsewhere. Always close the house’s main water valve before you begin working on a faucet. Remove the faucet’s handles to expose the valve stems or cartridges and to check for calcium buildup. Soak the valve stems or cartridges in vinegar and scrub them clean to get rid of deposits. You may need to remove the whole faucet if the inside of the spout is still clogged and then submerse the entire faucet in vinegar. You may need to leave the faucet in the vinegar overnight, depending on the extent of the hard water deposits.
Restoring Water
How you open the house’s main water valve after you perform any plumbing repairs can cause extra calcium deposits to accumulate in your faucets. The deposits may accumulate on the inside of your house’s water supply pipes. If you open the house’s main water valve quickly, the water rushes into the pipes with enough force to break the calcium deposits loose. Opening the main water valve slowly causes the water to flow into the pipes with less force.