Rheem Marathon MR105/473185 Use & Care Manual page 11

TIME / TEMPERATURE RELATIONSHIPS IN SCALDS
Temperature
120° F.
125° F.
130° F.
135° F.
140° F.
145° F.
150° F.
155° F.
RESETTING THE UPPER THERMOSTAT — It is recommended that the
upper thermostat remain at the factory setting for most normal applications.
All water temperature adjustments should be made at the lower thermo-
stat. If your application requires adjustment of the upper thermostat, it can
be changed as follows:
!
DANGER
Make certain power to water heater is OFF before removing jacket
access panel(s) FOR ANY REASON. Failure to do so could result in
property damage, bodily injury or death!
A. Remove the upper thermostat snap-in access panel cover. Insert finger
into latch hole on the bottom of the cover, and push up to release the
latch. Then pull forward to remove the cover and insulation. (See figure
10.)
Thermostat
Insulation (2)
Access Panel Cover
Cover
Insulation
Thermostat
Access Panel
Latch Hole
Figure 10 — Removing Upper Thermostat Access panel.
B. Remove the four (4) screws securing the thermostat access panel and
the two (2) thermostat insulation pads, exposing the thermostat. The
plastic personnel protector should not be removed .
C. With a small screwdriver, adjust the thermostat setting. This thermostat
is marked LOW / MED / HI. The 120°F factory set position (the recom-
mended setting) is at the 5 o'clock position (Refer to Figure 11). The
temperature settings range from approximately 110°F (LOW) to approx-
imately 170°F (HI). The MED position results in approximate water tem-
perature of 140° F.
D. Replace the two (2) pieces of fiberglass insulation over the thermostat
and attach the thermostat access panel.
Operation
Time to Produce Serious Burn
More than 5 minutes
1
1 / to 2 minutes
2
About 30 seconds
About 10 seconds
Less than 5 seconds
Less than 3 seconds
1
About 1 / seconds
2
About 1 second
Table courtesy of Shriners Burn Institute
Upper Thermostat
Access Panel Cover
Reset Button
HI setting equals approxi-
mately 170° F
water temperature.
Figure 11 — Upper Thermostat temperature adjustment.
E. Replace the single piece of fiberglass insulation inside the thermostat
access panel cover and snap in position.
NOTE: It is important that the fiberglass insulation is replaced to
maintain the water heater's high energy efficiency performance.
RESETTING THE LOWER THERMOSTAT — It is recommended that any
water temperature adjustment be made at the lower thermostat only. If
your application requires adjustment of the lower thermostat, it can be
changed as follows:
!
DANGER
Make certain power to water heater is OFF before removing jacket
access panel(s) FOR ANY REASON. Failure to do so could result in
property damage, bodily injury or death!
A. Remove the lower thermostat snap-in access panel cover. Insert finger
into latch hole on the bottom of the cover, and push up to release the
latch. Then pull forward to remove the cover and insulation. (See Figure
12.)
Thermostat
Insulation (2)
Access Panel Cover
Cover
Insulation
Thermostat
Access Panel
Figure 12 — Removing Lower Thermostat Access panel.
9
Temperature Adjustment
Screw (Shown at Factory Set-
ting of approx. 120° F.)
LOW setting equals
approximately 110° F
water temperature.
LOW
HI
MED
MED setting equals
approximately 140° F
water temperature.
Lower Thermostat
Access Panel Cover
Latch Hole