AERCO KC1000 Heater Mar 2011 - Manual (Page 38)

INITIAL START-UP
4-10
7. Press the CHANGE key. The display will
begin to flash.
8. Raise or lower the maximum load
adjustment using the ▲ or ▼ arrow key.
Increasing this value will increase outlet
water temperature, while decreasing it will
decrease water temperature.
9. Press ENTER to save the change. Allow
time for the system to stabilize between
adjustments
10. Repeat steps 5 through 9 as needed until
the temperature is stabilized 2 to 3 degrees
below the setpoint.
11. If the outlet temperature does not maintain
setpoint after a reasonable amount of time
and adjustment, contact your local AERCO
representative.
NOTE:
After performing Temperature Calibration and
prior to placing the water heater in service, be
sure to turn the Outlet Feedback option in the
Tuning Menu back to ON.
4.7 OVER TEMPERATURE LIMIT
SWITCH ADJUSTMENTS
There are two Over-Temperature Limit switches
that turn off the unit when the outlet water
temperature becomes too hot. The lower over-
temperature limit switch is adjustable and should
be adjusted 20°F to 40°F above the operating
header temperature. The upper over-
temperature limit switch is a manual reset device
and is not adjustable. It will shut the unit off if the
water temperature reaches 240°F. DO NOT
attempt to adjust its setpoint.
To adjust the lower over temperature switch limit
switch, proceed as follows:
1. Remove the wing nut from the top center of
the shell cap. Lift the cap off the shell.
2. The two over-temperature limit switches are
located at the top of the shell (Figure 4.5).
DO NOT adjust the upper switch which has
been factory preset. Adjust the lower switch
between 20°F to 40°F higher than the
maximum header temperature the unit may
reach.
3. Replace the shell cap and wing nut.
OVER-TEMPERATURE
SWITCHES
209
TEMPERATURE SWITCH DETAILS
137
HARNESS
136
FROM SHELL
NC
NC
C NO
C
25
OVER TEMP. SWITCH
(SEE DETAIL)
Figure 4.5
Over Temperature Limit Switch Location