23
Figure 10. Thermodisc
Thermostat
APCOM
INC
40A 120-277 VAC
25A.480 VAC
125VA.PT.DTY.
120-480 VAC
MED
LO
HI
MODE
L
WH19HC
30A 120-250 VAC
22A 277 VAC
12.5A 480VAC
125 VA.PT.DTY. 120-480 VAC
Figure 11. Apcom
Thermostat
Table 6 shows the approximate time-to-burn relationship for
normal adult skin.
Table 7. Time to Burn at Various Temperatures
Water
Temperature °F
T
ime for 1st Degree Burn
(Less Severe Burn
s)
Time for Permanent
Burns 2nd & 3rd Degree
(Most Severe Burns)
110
(normal shower temp.)
116
(pain threshold)
116
35 minutes
45 minutes
122
1 minute
5 minutes
131
5 seconds
25 seconds
140
2 seconds
5 seconds
149
1 second
2 seconds
154
instantaneous
1 second
(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong, Sept. 15,1978)
THERMOSTAT SETTINGS - ELECTRONIC CONTROLS
These models are equipped with an electronic control system.
The control system senses temperature from a factory installed
Immersion Temperature Probe (see
). The “Operating
Set Point” is adjusted to control water temperature. 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 - see
) located on the front panel of
the water heater.
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.
The Operating Set Point is adjustable from 90°F/42°C to
190°F/88°C. The factory setting is 120°F/49°C. See the
Electronic Control Models Operation section of this manual
for instructions on how to adjust the Operating Set Point and
other user settings.
Figure 12. UIM (User Interface Module)
Set the Operating Set Point at the lowest setting which
produces an acceptable hot water supply. This will always give
the most energy efficient operation.
Printed on 2/8/2018 9:05 AM CT
