3 adjusting the electronic control system, 1 adjusting the setpoint temperature, Ac-105 instructions - ecs & cxt-e – AERCO SWDW68 U-Tube Double-Wall Heaters w/ECS User Manual
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AC-105 INSTRUCTIONS - ECS & CXT-E
Rev B Mar 2013
4-3
4.3 ADJUSTING THE ELECTRONIC CONTROL SYSTEM
The ECS is factory set by AERCO to the setpoint temperature specified on the sales order. Normally, the
over-temperature alarm limit is set 20°F above the specified setpoint. If no setpoint or over-temperature
alarm limit is specified, the ECS is set to the factory default values of 140°F (setpoint) and 160°F (over-
temperature alarm limit).
To change the setpoint and over-temperature alarm limits, use the controls provided on the Temperature
Controller and the Over-temperature Switch. These controls are visible through the Control Box front door
window and can be accessed by opening the panel door (Figure 4-1).
4.3.1 Adjusting the Setpoint Temperature
Figure 4-3 illustrates and Table 4-1 describes the Temperature Controller controls and indicators. Use
these controls/indicators to adjust the setpoint temperature as follows:
1. Turn the Control Box power switch on and open the Control Box door.
2. Wait approximately 3 seconds while the Temperature Controller performs its self-test. When the test
is completed, the upper display will indicate the current heat exchanger Hot Water Output
temperature, and the lower display will indicate the setpoint temperature stored in memory
(default = 140°F), as illustrated in Figure 4-3.
3. Ensure that the Temperature Controller is set to the AUTO(matic) mode and the AUTO indicator is lit.
If the MAN(ual) indicator is lit, press the AUTO/MAN pushbutton to toggle the mode setting. Indicator
OP1 should also be lit.
4. Press the
▲ or ▼ arrow buttons, as necessary, to change the display to the desired value.
5. Two seconds after the
▲ or ▼ arrow button is released, the display will blink to indicate that the
Temperature Controller has accepted and stored the displayed value.
AUTO
RUN
MAN
HOLD
OP 1
OP 2
SP2
REM
2408
UPPER DISPLAY
(DISPLAY HOT
WATER OUTLET
TEMPERATURE)
AUTO
SETPOINT
MAN
VALVE % OPEN
AUTO/MAN MODE
INDICATORS
AUTO/MAN
PUSHBUTTON
OP1 INDICATOR
ARROW
BUTTONS
LOWER DISPLAY
MODE
DISPLAYS
Figure 4-3. Temperature Controller