If you are asking which one you leave on to keep the pipes from freezing in the winter time the answer is that it depends. First, most houses today don't have this problem. The supply lines in the yard are buried deep enough not to freeze and the houses are insulated well enough for interior pipes not to freeze if the house is occupied.
If you own an older home then you may have to worry about this. If you are worried about the supply pipe in the yard that brings water to the house not being buried deep enough so that it could freeze, then you only need to leave open a cold water tap to drip.
If you have pipes in your walls or under your house that you think might freeze then you need to let both hot and cold drip.
To adjust the shower knobs for the desired water temperature and pressure, turn the hot and cold knobs until you reach the desired temperature. Adjust the pressure by turning the knobs to increase or decrease the flow of water.
When your pipes freeze, you should turn off the water supply and use a heat source like a hairdryer to thaw them slowly. To prevent freezing in the future, you can insulate your pipes, keep your home heated, and let faucets drip during cold weather.
Of course as water is heated it expands and some faucets such as American Standard with the CAP WASHER sometimes open slightly and allow water to drip
The main benefit of a mixer shower is that the hot and cold water is mixed without having to turn two knobs. People don't have to mess with different knobs to get the right water temperature for their shower.
To achieve the perfect water temperature in the shower, adjust the hot and cold knobs until you reach a comfortable balance between the two extremes. Turn the hot knob clockwise to increase the temperature and the cold knob counterclockwise to decrease it. Keep adjusting until you find the ideal mix for your preference.
You need to turn it off at the base of the sink. Or depending on the problem you may need to turn it off at the water main valve.
To replace shower knobs, first turn off the water supply. Remove the existing knobs by unscrewing them. Install the new knobs by screwing them in place and turning the water supply back on. Test the knobs to ensure they are working properly.
The knobs on the bottom of the toilet hold the toilet to the bolts that in turn hold the toilet in place on the floor.
Technically it won't matter as the hot water is made from incoming cold water. However it would be cheaper to turn on the cold water and let it run very slowly, more than a drip. If you leave the hot open, the heater will be turning on and off all night.
Turn up the heat after opening the faucets (TAPS)
Water hammer. It can be harmless.
If your pipes freeze, you should first turn off the water supply to prevent further damage. Then, you can try to thaw the pipes using a hairdryer or heating pad. To prevent this issue in the future, you can insulate your pipes, keep your home heated to a consistent temperature, and let faucets drip during very cold weather to keep water flowing.