Temperature Regulation

High Temperature Limit Control (ECO)

This water heater is equipped with an ECO (energy cut off) non adjustable high temperature limit switch. The ECO is a normally closed switch that opens (activates) on a rise in temperature.

The ECO is located inside the Upper Temperature Probe (two red wires), see Figure 3 on page 41 for location. The ECO switch contacts will open when the water temperature reaches approximately 202°F (94°C) and close at approximately 140°F (49°C).

If the ECO activates (contacts open) due to abnormally high water temperatures in the storage tank the control system will immediately de-energize the 24 VAC Gas Valve and end the current heating cycle. The control system will "lock out" disabling further heating operation. The control system will display the "Energy Cut Out (ECO)" Fault message on the LCD screen. It is important that a Qualified Service Agent be contacted to determine the reason for the ECO activation before resetting the ECO. Once the reason has been determined and corrected the ECO can be reset as follows:

Should the ECO activate, the water temperature must drop below 140°F (49°C) before the control system can be reset. Once the water temperature has cooled below this point the power supply to the water heater must be turned off and on again to reset the control system.

Thermostat Control

Water temperature over 125°F (52°C) can cause severe burns instantly resulting in severe injury or death.

Children, the elderly and the physically or mentally disabled are at highest risk for scald injury.

Feel water before bathing or showering.

Temperature limiting devices such as mixing valves must be installed when required by codes and to ensure safe temperatures at fixtures.

Hot water temperatures required for automatic dishwasher and laundry use can cause scald burns resulting in serious personal injury and/or death. Table 10 shows the approximate time-to- burn relationship for normal adult skin.

The temperature at which injury occurs varies with the person’s age and duration of exposure. The slower response time of children, the elderly or disabled persons increases the hazards to them. If anyone using hot water provided by the water heater being installed fits into one of these groups or if there is a local code or state law requiring a certain water temperature at the point of use, then special precautions must be taken.

In addition to using the lowest possible temperature setting that satisfies the demand of the application a mixing valve can be installed at the water heater (see Figure 8 on page 41) or at the hot water taps to further reduce system water temperature.

Never allow small children to use a hot water tap or draw their own bath water. Never leave a child or disabled person unattended in a bathtub or shower.

The water heater should be located in an area where the general public does not have access to set temperatures.

Setting the Operating Set Point at 120°F (49°C) will reduce the risk of scalds. Some States require settings at specific lower temperatures.

Table 10

Water Temperature

Time to Produce 2nd & 3rd

Degree Burns on Adult Skin

 

180°F (82°C)

Nearly instantaneous

170°F (77°C)

Nearly instantaneous

160°F (71°C)

About 1/2 second

150°F (66°C)

About 1-1/2 seconds

140°F (60°C)

Less than 5 seconds

130°F (54°C)

About 30 seconds

120°F (49°C)

More than 5 minutes

The water heaters covered in this manual are equipped with an electronic control system to regulate the water temperature inside the storage tank. The control system senses temperature from two factory installed temperature probes, one installed in the top of the storage tank and one installed near the bottom, See Figure 3 on page 41 and Figure 4 on page 41 for location.

The “Operating Set Point” is adjusted to regulate water temperature inside the storage tank. This is an adjustable user setting in the control system’s “Temperatures Menu.” This and all control system menus are accessed through the UIM (user interface module) located on the front of the water heater, see Figure 54.

The Operating Set Point is adjustable from 90°F (42°C) to 180°F (82°C). The factory setting is 120°F (49°C). See Operating Set Point And Differential Adjustment on page 41 for instructions on how to adjust the Operating Set Point and other user settings.

Set the Operating Set Point at the lowest setting which produces an acceptable hot water supply. This will always provide the most energy efficient operation.

High Temperature Applications

Higher operating temperatures cause more wear on all water heaters and will decrease the life span of the appliance. Consider installing a small booster water heater for high temperature applications, such as commercial dishwashers, to raise the outlet temperature from the larger primary water heater to the desired point of use temperature.

Contact your local distributor or call the technical support phone number listed on the back cover of this manual for further technical assistance.

MANUFACTURER / MODEL INFORMATION

 

Tank Temperature

 

103°F

UP

Operating Set Point

 

120°F

 

 

Status: Heating

 

 

 

OFF

 

 

DN

GAS

O

 

 

N

 

 

MENU

 

HELP

 

Figure 54

41

Page 41
Image 41
State Industries SUF-130- 300/400/500 Temperature Regulation, High Temperature Limit Control ECO, Thermostat Control