Service manual

MSE Series Electric Boilers – Installation and Service Manual
10
BC-1 Controller Information Section 5
WARNING
The following section is intended as a quick reference guide for the BC-
1 Controller Manual.
Read all instructions and the BC-1 Controller Manual before placing the boiler in operation or
making any adjustments. Adjustments must be made by a qualified heating technician.
5.1 CONTROLLER INFORMATION
Control Board Dimensions:
4-3/4” (L) x 2-7/8” (W) x 1-7/8” (H).
Power Outputs:
Pump output from P1 P2 terminals on the pump terminal
block is 120 Vac, 60 Hz, 5 A max. These terminals can
provide an automatic on/off switching power supply to the
boiler pump or a pump contactor. The load current of this
output is limited by the pump fuse selected (boiler supplied
with 3 A fuse) and must not exceed 5 A or 600 VA.
Boiler Stage outputs from Stg1&Stg1, Stg2&Stg2 and
Stg3&Stg3 terminals are 24 Vac, 60 Hz.
Alarm output from AL&AL terminals is 24 Vac, 60 Hz,
0.45 A maximum.
Signal Inputs/Controls (Do not apply external power):
HT&R: Room thermostat or zone valve end switch,
24Vac switching input, closed is activation.
ST&R: Setpoint DHW aquastat, 24Vac switching input, closed is activation.
FS&FS: Flow switch, 24Vac switching input, closed is activation.
HL&HL: High Limits, 24Vac switching input, open at 239°F, automatic reset.
Thermistor Sensors
BO&CM: Boiler outlet sensor
BI&CM: Boiler inlet sensor
OS&CM: Outdoor sensor
SD&CM: Supply / DHW sensor
Figure 4 – BC-1 Controller