Fire Coil 85
(500-2000)
Page 21
volt single-phase power to the terminal marked “120V
(L2)” and supply the pump using the terminal marked
“L2 LOAD (EXT. PUMP)”.
NOTE:
This pump control is equipped with a delay on
break typically set for 3 minutes, but can be adjusted
between 0.1 and 10 minutes.
Field Interlocks:
To install other field-wired
devices to interlock with the boiler (tank stats, louver
switches, flow switches, etc.), remove the jumper
between terminals 3 and 4 and wire the device in series
across these terminals. These terminals are located in
the upper main control panel.
External Control Wiring:
These terminals are
located in the upper main control panel (see
Section 5.3
).
Optional Alarm Contacts:
As an option, the Fire
Single pole switches, including those of safety
controls and protective devices must not be wired in a
grounded line.
All electrical connections are made in the field
wiring terminal strip, which is located at the right side of
the appliance.
NOTE:
All internal electrical components have been pre-
wired. No attempt should be made to connect electrical
wires to any other location except the wiring box.
5.1 Main Power
The Fire Coil 85 main power requires a 120-volt
fused supply that is connected to the “main power” terminal
strip. The over current protection must be sized as specified
(see
Figure 15
).
The MT2 pump (pump-mount units) requires a
separate (additional) 120-volt fused supply connected to
the pump terminal strip (also specified in
Figure 15
).
5.2 Field Wiring
Main Power:
The main 120V field wiring panel is
located on the right side of the unit, under the main
power switch. Within this panel are the terminals for
incoming 120V single-phase power clearly labeled on
the right-hand side as “120V (L1)”, “NEUTRAL” and
“GROUND”.
Pump Power:
Also located on the 120V field
wiring panel is the pump terminal strip. This strip is
located on the left side (denoted as “120V L2”, “N2
(Pump mounted)” and “GROUND 2 (Pump Mounted)”).
External Pumps:
External Pump: All non-pump-
mounted MT2 units have an internal (dry) contact rated
for 20Amps. A field-supplied pump can be connected
directly to this contact if it does not draw more than 20
Amps. If more current is required, a separate pump
contactor must be installed.
To utilize this internal pump contact, supply 120
Figure 16. Fire Coil 85 (500–750) Wiring Diagram.
Figure 15. Field Wiring.
UNIT SIZE
PUMP CIRCUIT
MAIN CIRCUIT
500
15A
15A
750
15A
15A
1000
15A
20A
1250
15A
20A
1500
15A
20A
1750
15A
20A
2000
20A
20A
Summary of Contents for Fire Coil 85
Page 23: ...Fire Coil 85 500 2000 Page 23 Figure 19 Fire Coil 85 500 750 Connection Diagram ...
Page 24: ...National Combustion Co Inc Page 24 Figure 20 Fire Coil 85 1000 Connection Diagram ...
Page 25: ...Fire Coil 85 500 2000 Page 25 Figure 21 Fire Coil 85 1250 2000 Connection Diagram ...
Page 37: ...Fire Coil 85 500 2000 Page 37 Figure 23 Sheet Metal Components ...
Page 38: ...National Combustion Co Inc Page 38 Figure 24 Internal Components ...
