Have you ever tried to use someone else’s shower and found yourself wondering, “is hot up or down on a faucet?” You’re not alone.
This is a common question many people have, especially when they encounter a faucet they’re unfamiliar with.
The hot and cold knob dilemma is a gray area in plumbing. While there’s no universal consensus among inspectors, contractors, or plumbers, there are some general guidelines.
For most faucets, the hot water is on the left side, making the “what side is hot water on a faucet?” a fairly easy question to answer.
For most faucets – hot is left, and cold is right. It’s been the industry standard for over 100 years. Manufacturers like Delta, Kohler, and Moen make single-lever faucets that all follow this convention.
But when it comes to faucets where the handle only moves up or down, which handle is hot water?
On kitchen faucets like the Moen Align Pulldown, where the handle is mounted vertically on the side, it’s the same. Left is hot, and cold is right. In other words, counterclockwise (towards you) is hot, and clockwise (away from you) is cold.
The design choice of which side is hot and cold on a faucet is often attributed to safety considerations. The prevailing thought is that since most of the population is right-handed, they would naturally gravitate towards the cold handle first.
The rationale is that it’s preferable to be momentarily startled by cold water than to risk burns from hot water.
However, it’s debatable how many actually burn themselves due to mistakenly turning the hot handle.
For those who are left-handed, this design might feel like another instance where the majority’s preferences overshadow theirs. If we follow this logic consistently, shouldn’t all door handles be on the right?
And why do toilet flush handles predominantly sit on the left? While the reasoning might seem puzzling, the good news is that switching between hot and cold is a straightforward process that can be done in just a few minutes.
How to Switch Hot and Cold Water Lines
One of the easiest ways to switch the hot and cold handles is to switch the water lines. There are two supply lines located under your sink, one for hot and one for cold. All you will be doing is turning a wrench.
Look underneath your sink and locate the cold and hot water shutoff valves. They are two oval-shaped chrome knobs. Each one is attached to a metal water line that runs back up to the faucet.
To shut off the water, turn the knob counterclockwise. After you shut off the water supply, turn on the faucets to make sure the water is off.
Next, you can switch the water supply lines. Use a wrench to unscrew the nut holding the supply line to the pipe by turning it counterclockwise. Reattach the supply lines in the opposite order and tighten them. Make sure you are screwing them on straight, or else it will leak.
Now turn on the shutoff valves to test for leaks. If there is a leak, shut it off right away, remove the nut, and retighten it. Test it again.
If your handles have indicators on them (i.e., cold is blue, red is hot), you will want to switch those if you can.
How to Make a Hot Water Adjustment to Find the Perfect Temperature
Another common issue with single-handled faucets is with the temperature. If the water is coming out too hot or too cold, you may need a hot water adjustment. If you want to adjust the temperature, you can change the ratio of hot and cold water (the mixture). All you need is a screwdriver.
Adjust Water Mixture
First, use a screwdriver to remove the handle. How it’s put together depends on the make and model of your faucet. Typically you will either pry off the small plastic cover over the screw or there will be a screw somewhere under the handle.
Next, you can adjust the mixture. Your faucet will have one or more adjustment screws underneath the handle. Some faucets have a dial.
If your faucet has a screw, turn it counterclockwise to increase the amount of hot water in the mixture and clockwise to increase the amount of cold water.
If your faucet has a dial or a nub, you can use your hand or a pair of pliers to move it. Similarly, turning the dial counterclockwise will increase the amount of hot water in the mixture and clockwise to increase the amount of cold water.