If the temperature of the water in your shower is not to your liking, you could consider some minor adjustments. Being comfortable when you bathe is important, and with adherence to a few safety guidelines, it's possible to alter the temperature of the water in your shower yourself. You'll need a basic understanding of how your shower works and a few tools.
Checking the Water Temperature
If your shower has been providing water that's too hot or too cold, there are simple steps to make things more comfortable. Water temperature in your shower is controlled by something called the rotational limit stop position of your shower valve cartridge – or anti-scald valve. This limits how far the shower knob can rotate, which, in turn, controls the available temperature range. In general, the hot water handle should be set so that when you turn it as far as you're able, it reaches a temperature that is comfortable and won't scald you.
To access the shower valve cartridge, you'll need to remove the faucet head. The shower valve cartridge is situated between the hot and cold handle inputs. With the valve in the "off" position, point your shower head away from yourself. Since you'll be manipulating the water temperature, you don't want to get wet as you might get scalded.
Next, press the shower handle on the stem of the shower valve cartridge and hold it so that it is secure. Carefully turn the handle as far as it will go in the "hot" position. Once the temperature of the water stops changing, test it cautiously. If you're happy with the temperature as is, you can reassemble the faucet.
Delta Faucet Temperature Adjustment
If you'd like to make changes your Delta shower faucet's hot water adjustment, you'll need to change the rotational limit stop. To do this, push the trim sleeve inward a bit. Remove the gray disc from the brass cartridge stem. This is what holds the rotational limit stop. You should be able to just slide the disc off.
Next, rotate the rotational limit stop in a counter-clockwise direction to make the water hotter and a clockwise one to make it colder. If you forget which way to turn, the directions should be marked on the unit. Make your Delta faucet temperature adjustment slowly. Test the water to verify if it's at a comfortable temperature. Do this by turning the shower on and carefully putting the water at its full "hot" position. Continue with this process until you have achieved the temperature you find ideal.
Hot Water Heater Adjustment
In general, a comfortable water temperature for most people is 120 degrees Fahrenheit. This may be different for children or the elderly, who may be unable to tolerate such heat. Check the settings on your hot water heater to determine whether it is set above or below your optimal temperature.
First, turn off the power to the hot water heater. You can accomplish this by switching off the associated circuit in your breaker box. Let others in the house know about the project you are undertaking and ask that they refrain from changing the breaker set-up or using the water until you have finished.
Next, use a Phillips head screwdriver to remove the panel that covers the hot water heater's temperature dial. The panel should be marked to indicate what it does. You'll then need to remove the insulation behind the panel. This will give you access to the temperature setting. Use a flat head screwdriver to adjust the temperature setting. Finally, replace the insulation and cover. You can then restore power to the hot water heater. Test out the temperature and be sure that it's as you prefer. If not, you can make additional adjustments at the hot water heater level.