Troubleshooting: Water temperature is not HOT enough on tub shower units

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Typical Cause

Hot water may not be supplied to the valve, a balancing spool may be stuck or the temperature may be calibrated not to allow full hot water (up to 120 degrees Fahrenheit).

Solution

First, if external shut off valves are present, verify they are opened all of the way. It is extremely important that the units have both hot and cold water supplied to the inlets of the valve body. Also, verify the hot water system in the home is on.

Second, it is essential to identify the model of your faucet. Please view our Find Your Product section to determine your model.

Note: If comparing the temperature of the water to an adjacent lavatory faucet, you may notice the temperature may not be as hot (or as cold) in the tub/shower valve.

Also, depending on your climate, the incoming water (ground water) temperature may fluctuate during the year. This can cause the overall hot temperature to decrease (or increase) throughout the year.

For Posi-Temp models:

  1. If the water pressure decreases when going from cold to hot, the 1222 cartridge would need to be replaced.
  2. Verify the handle rotates all the way counter-clockwise to a 9 o'clock position. If the handle stops before this position, then the temperature limit stop will need to be re-positioned. Please view the installation instructions for assistance on how to set this.
  3. If the issue is still unresolved, replace the 1222 cartridge and flush the valve body.

For Moentrol Models:

  1. Inspect the 1423 balancing spool. This will appear on the front of the valve body, either to the right or above the cartridge. It will look similar to a large flat head screw, and it will be brass in color about the size of a quarter. A large flat-bladed screwdriver can be used to unscrew the balancing spool from the valve. There will be a spool inside this piece, and it needs to move freely inside of its shell. If the spool does not move freely, then the 1423 balancing spool will need replaced.
  2. Verify the top of the handle rotates all the way to a 9 o'clock position. If the handle stops before this position, then the adjustable temperature limit stop will need to be adjusted to allow the handle to rotate all the way to the hot position. Please view the installation instructions for assistance on how to set this.
  3. If the issue is still unresolved, replace the 1225 cartridge and flush the valve body.

For ¾" ExactTemp models:

Note: For ½" ExactTemp valves refer to original service manual.

  1. Make sure the remperature override button is being pressed in. If calibrated properly, the handle will hit a stop at 105 degrees. In order to get warmer temperatures, the temperature override button needs to be pushed in and then the handle will be able to rotate counter-clockwise to warmer temperatures.
  2. Verify the stops are opened. The stops are located on the inlets of the valve, and they look like small flat head screws. Use a flat head screwdriver to unscrew this counter-clockwise until you reach a stop, this will ensure it is opened all of the way (screwing clockwise until a stop is reached will turn the water off).
  3. The cartridge may need to be calibrated. Instructions on calibration can be obtained via the ExactTemp Service Manual in our Literature Center.

For ioDigital models:

  1. Make sure the temperature knob is being rotated to the hot side. The corresponding LEDs with light red to illustrate this.
  2. Verify that both shut off valves are in the open position. These will vary depending on your ioDigital model.
  3. Verify the hot water supply is attached to the hot water side and the cold water supply is on the cold side. Feel the temperature of the inlet lines. If the hot is going to the cold side and the cold is going to the hot side, the lines will need to be reversed.
  4. Remove the valve inlet screens and inspect for any debris. The water supply will need to be shut off, and then the black nut on the inlets can be unscrewed to remove the inlet screens. Rinse off any debris that may be on these screens and reinstall.
  5. The maximum temperature adjustment setting will need to be calibrated. This can be identified as a blue dial on the valve labeled "Max Temp Adjustment" This can be rotated clockwise to increase the maximum temperature (counter-clockwise will decrease the temperature).

Note: The maximum temperature is factory preset at 115 degrees Fahrenheit.