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Modulex EXT Commercial Series Boilers User Manual
CHAPTER 4: Installation Instructions
Page
74
of
144
AERCO International, Inc.
•
100 Oritani Dr.
•
Blauvelt, NY 10913
OMM-0095_0H
09/15/2017
Phone: 800-526-0288
GF-139
4.38 CONTROLS AND EMERGENCY FUNCTIONS
Figure 4-34: MODULEX EXT Panel Controls and Indicators
TABLE 4-8: Panel Controls and Indicators
ITEM
COMPONANT/FUNCTION
A
GLT (General Limit Thermostat): when enabled, it cuts the power supply to the
boiler and lights the warning lamp (Item D). To reset, remove the cap and push
the reset button.
B
Main Power Switch
C
Fuses: 1 = 6.3 A 2 = 10 A
D
Warning lamp of the Thermostatic
Lockout from GTL (General Limit Thermostat).
E
Main Switch
F*
Change-over Series/Parallel:
0 = Emergency is active or the control is managed by PLC or BMS.
I = Series connection (the cascade is managed by the BCM)
II = Parallel connection (condition of supply).
G*
In position “I” the plant will operate when requested at “CONSTANT SETPOINT”:
70°C –
Max heat output 50%.
H*
Enables burner reset in case of lock-out.
I*
YELLOW LED = Blinking = Communication between BMM and BCM is OK.
GREEN LED = ON = Active Pump
RED LED = ON = Failure Code Detected
*See Chapter 5, section 5.2 for more information regarding the BCM (Boiler Communication
Module).
NOTE:
The emergency function enables the boiler’s burners to fire only at 50% and at 50°C in system
return. All the system’s heating loads, including the header pump, must be controlled manually.