AERCO Electronic Controls System (ECS) - Manual (Page 27)

Electronic Control System (ECS) and Type CXT-E Valve
3. ADJUSTMENT
VD2: 02/28/14 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 • Phone: 800-526-0288 Page 27 of 82
AC-105 OMM-0003_0D
3.3 ELECTRONIC CONTROL SYSTEM (ECS) ADJUSTMENT
The Electronic Control System (ECS) is preset at the setpoint temperature specified on the
Sales Order. The over-temperature alarm limit is normally set 20°F above the specified setpoint.
If no setpoint or over-temperature alarm limit is specified, the ECS will be set to the Factory
Default values of 140°F (setpoint) and 160°F (over-temperature alarm limit). If changes are
required, the setpoint and over-temperature alarm limits can be easily changed. This is
accomplished using the controls provided on the Temperature Controller and the Over-
Temperature Switch contained in the Control Box shown in Figure 3-2. These items can be
viewed through the window on the front door of the Control Box. To access these controls and
adjust the setpoint or over-temperature alarm limit, open the hinged Control Box door. Proceed
as follows to adjust the required parameters:
NOTE:
For “Water-to-Water” Heater applications, two additional
Temperature Display Indicators are mounted below the Over Temp
Switch. Although these Indicators are identical to the Over Temp
Switch, they are “Indicator-Only” devices which cannot be adjusted.
WATER HEATER
TEMP CONTROLLER
B-PLUS TM
HOLD
RUN AUTO
MAN
2408
PT.NO.
PT.NO.
OVER TEMP SWITCH
PANEL
DOOR
OVER-TEMP
SWITCH
TEMPERATURE
CONTROLLER
Figure 3-2. Control Box – Front View
NOTE:
When the Power Switch on the Control Box is set to the ON position,
it also energizes the internal DC Power Supply in the Control Box.
This in turn provides 24 VDC power to the Control Valve Actuator,
provided that the water temperature at the heater outlet is below the
high temperature limit setting.