MACH® Series
Gas-Fired Boiler
Parts and Technical Support
Page 37
6.2
W
IRING
D
IAGRAMS
6.2.1a Terminal Block Assignments – High Voltage Circuit (TB2)
Terminal Number
Label
Description
1
115 VAC LINE
2
115 VAC NEUTRAL
Boiler Supply Power, 115 VAC, 60 HZ, 1 ph, 8 amp
3
115 VAC NEUTRAL
Aux. Switched Output
4
115 VAC NEUTRAL
Boiler Circ. Pump
5
115 VAC NEUTRAL
DHW Circ. Pump
6 GROUND
Boiler
Supply
Ground
7 GROUND
8 GROUND
Aux .Ground
9
115 VAC SW. OUTPUT
Aux. Switched Output, Pilot duty only, 1 amp max.
10
115 VAC CIRC. PMP
CONTACTOR
Boiler Circ. Pump, Pilot duty only, 1 amp max.
11
115 VAC DHW PMP
CONTACTOR
DHW Circ. Pump, Pilot Duty only, 1 amp max.
12
MASTER ALARM RELAY
13
MASTER ALARM RELAY
Dry Contacts, 24 VAC max, 1 amp max.
14
THREE WAY VALVE RELAY
15
THREE WAY VALVE RELAY
DHW Dry Contacts, 24 VAC max, 1 amp max.
16 DAMPER
RELAY
17 DAMPER
RELAY
Combustion Air Damper, Dry Contacts, 24 VAC max, 1 amp
max.