Temperature Regulation; High Temperature Limit Controls (Eco); Thermostat Controls; Thermostat Settings - Surface Mount Control - State Water Heaters 100 Series Instruction Manual

hIGh teMperature lIMIt controls (eco)

Both the ELECTRONIC CONTROL and SURFACE MOUNT
CONTROL model water heaters are equipped with one or more ECO
(energy cut off) non adjustable high temperature limit control(s). An
ECO is a normally closed switch that opens (activates) on a rise
in temperature. If the ECO switch contacts open (activate) due to
abnormally high water temperatures it will lock-out and disable further
heating element operation. 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(s) can be reset as follows:
surface Mount control Models
Surface Mount Control models have multiple surface mounted
Thermostat/ECO combination controls. One for each installed heating
element - see the Surface Mount Control wiring diagrams in this
manual. The ECO high temperature limit switch contacts on each
control will open when the tank temperature reaches approximately
200°F/93°C. If activated, the ECO reset button will be slightly extended
and stiff to the touch. When the ECO switch contacts open (activate)
voltage to ONE heating element ONLY is terminated to prevent further
heating operation of that element. Voltage may still be present at other
heating elements and they may still be heating the water.
The ECO is a manual reset switch. Should one or more ECO activate,
the tank temperature must drop below 120°F/49°C before an ECO
can be reset. To manually reset an ECO:
1. Disconnect the power supply to the water heater.
2. Allow the tank temperature to cool below 120°F/49°C.
3. Remove the front control cover from the effected control(s).
4. Press the manual reset button on each of the effected controls.
5. Once the control(s) has been reset the control cover should be
replaced prior to restoring power to the water heater.
electronic control Models
The ECO high temperature limit switch is located inside the
immersion Temperature Probe (two red wires) on ELECTRONIC
CONTROL models. The ECO switch contacts will open when the
water temperature reaches approximately 202°F/94°C. When the
ECO switch contacts open (activate) the electronic control system
locks out and displays a Fault message. Voltage to the contactor
coils and heating elements is terminated to prevent further heating
operation.
Should the ECO activate, the water temperature must drop below
140°F/60°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 controls

The water heaters covered in this instruction manual are equipped
with adjustable thermostat controls to control water temperature. Hot
water temperatures required for automatic dishwasher and laundry
use can cause scald burns resulting in serious personal injury and/
or death. The temperature at which injury occurs varies with the
persons age and duration of exposure. The slower response time
of children, the elderly or disabled persons increases the hazards to
them. 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 water heater temperatures at 120°F (49°C) will reduce risk of
scalds. Some areas require settings at specific lower temperatures.

teMperature reGulatIon

therMostat settInGs - surface Mount control

Adjustment of temperature controls on surface mounted controls is
to be performed by a qualified service agent at initial start-up.
These models have multiple thermostat/ECO combination controls
one for each heating element installed. These thermostats are set
from the factory at 140°F/60°C. Set the thermostat dial at the lowest
setting which produces an acceptable hot water supply. This will
always give the most energy efficient operation.
The water heater is supplied with thermostats that may come from
different manufactures and have different temperature indications
as described below.
thermodisc
Thermodisc thermostats are adjustable from approximately 120°F
(49°C) (lowest setting) to 180°F (82°C) (highest setting) see figure
7A. These thermostats are set from the factory at approximately the
140°F (60°C) setting. The over temperature device (ECO high limit)
attached to each thermostat has a manual reset.
apcoM thermostats
Apcom thermostats have three designated set points; LO, MED and
HI. See figure 7B.The approximate equivalent temperatures for these
three settings are: LO = 140°F (60°C), MED = 160°F (71°C) and HI
= 180°F (82°C). These thermostats are set from the factory at the
LO 140°F (60°C) setting. The over temperature device (ECO high
limit) attached to each thermostat has a manual reset.
fIGure 7a.
Table 7 shows the approximate time-to-burn relationship for normal
adult skin.
taBle 7.
Water Temperature
180°F (82°C)
160°F (71°C)
150°F (66°C)
140°F (60°C)
130°F (54°C)
120°F (49°C)
80°F (27°C)
33
40A 120-277 VAC
25A.480 VAC
125VA.PT.DTY.
120-480 VAC
LO
HI
MED
APCOM
INC
30A 120-250 VAC
22A 277 VAC
12.5A 480VAC
125 VA.PT.DTY. 120-480 VAC
fIGure 7B.
Time to Produce 2nd & 3rd
Degree Burns on Adult Skin
Nearly Instantaneous
About 1/2 second
About 1-1/2 seconds
Less than 5 seconds
About 30 seconds
More than 5 minutes
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