Many homes have ``air chambers'' in the pipes to help absorb water hammer but over time they tend to stop working or get waterlogged and you can clear them by draining the water. You can also put water hammer arresters on your washing machine and dishwasher to help.
This can be fixed by retrofitting a water hammer arrestor. The arrestor acts like a mini expansion vessel and gives the pressurised water somewhere to go, thereby reducing the pressure. Lower pressure equals less hammer-like noise!
Flush cold water.
Run all cold-water faucets on the property beginning with the faucet closest to the water line. Let all run at the highest flow (or fully open) until water is clear and temperature is constant. Then turn off all faucets in reverse order.
Ideally, to protect from freeze damage, the water supply should be shut off and the pipes should be purged (drained) of water.
Pipes: Turn off water supply to the house and drain pipes to protect them from freezing. You can empty pipes by running the water and flushing the toilets after the water has been turned off. After draining the pipes, it is a good idea to leave the faucets open to prevent pressure build up from any water that remains.
The question of dripping every faucet needs context. You can drip just one if it's further from the water line. If you are unsure where that is, dripping all of them is a good option. It might cost you extra on your water bill, but plumbing repair and damage of a busted pipe in your home could cost even more.
Begin the flushing procedure by opening the hot water taps in your bathroom(s). Open ALL hot water lavatory (sink) fixtures, hot water bath fixtures, and any other hot water fixtures, such as kitchens, wet bars, etc. Run these hot water fixtures for at least 15 minutes. Shut water off after 15 minutes.
If you never had hammering and then it suddenly starts, most likely your plumbing system's air chambers have become waterlogged. You can cure water hammer by turning off the water behind the waterlogged chamber, opening the offending faucet and permitting the faucet to drain thoroughly.
The easiest way to prevent and fix a water hammer is to create a space before the outlet filled with gas or air that can absorb the pressure. In older homes, this was originally accomplished by creating an air chamber, a piece of capped-off vertical pipe near the outlet.
If you have water hammer or experience any of the above issues from water hammering, contact your plumber immediately to assess the health of your pipes, joints, and valves. Your plumber will also give you options for fixing the problem.
How long does it typically take to drain an average home's plumbing system? The duration varies depending on the size of the house, the complexity of the plumbing system, and the water flow. However, for an average-sized home, it might take anywhere from 30 minutes to a couple of hours to fully drain the system.
Install air chambers
Air chambers are also an effective solution to water hammer. These systems consist of a short segment of pipe with an empty/air filled chamber that cushions shock waves. This reduces the size of the shock waves downstream of the valve.
Line flushing is a process which uses highly pressurized water to remove sediment from water lines, and is one of the most effective ways to clean pipes. Sediment builds up in areas that are often difficult to get to, and can block different parts of various pipes.
First, close all open faucets. Turning off the water off to your home at the water main can introduce air into the pipes. To make sure you don't damage the plumbing system, always slowly turn the water back on by gradually turning the main water valve handle back to the open position. Never turn the handle quickly.
A straightforward drain cleaning job, such as unclogging a sink or toilet, typically takes about 30 minutes to an hour. However, if the blockage is severe or located deep within the plumbing system, it could take several hours or even a full day to resolve.
Prevent Frozen Pipes
Moving water keeps pipes from freezing. Find shut off valves for emergencies. Insulate pipes in unheated areas. Open cupboards and vanities to warm pipes.
If you live in a climate with freezing temperatures, you'll want to cover your outdoor faucets in the winter rather than dripping them. Even with a vigorous drip, frigid temperatures can travel through your faucet and freeze the connecting pipes. Before using a cover, you'll need to properly winterize your faucet.
Frost becomes more widespread when the temperature falls below 32°F with some freeze possible. A hard freeze is possible when temperatures fall below 28°F.