Parts/Technical Support; Schematic Diagrams - Harsco Industrial MODU-FIRE FORCED DRAFT N750 Installation & Owner's Manual

6.0

PARTS/TECHNICAL SUPPORT

Spare and replacement parts can be ordered from your local representative or Harsco Industrial, Patterson-Kelley by
calling (877) 728-5351. The fax number is (570)476-7247. Refer to the parts list shown on the assembly drawing
provided with this manual. Factory direct replacement parts must be used to ensure that the boiler operates correctly.
Technical information is also available at the above number or at the Harsco Industrial, Patterson-Kelly website
www.harscopk.com. When ordering replacement parts please have the model number and serial number of your
boiler available.
equipment. All control components are engineered for safety and are designed to work in unison with
each of the other components. Use of non-factory-authorized replacement parts would jeopardize the
functionality of the safety features as well as the performance of the boiler.
6.1 S D
CHEMATIC IAGRAMS
Typical schematic drawings are shown on the following pages. Drawings specific to your particular boiler can be sup-
plied by your local Harsco Industrial, Patterson-Kelley representative.
6.1.1 Terminal Block Assignments - High Voltage Circuit (HV)
Terminal Number Label
1 L1 208-240 V
2 L2 208-240 V
3 N 208-240 V
4 120 VAC Switched Output Neutral Line for HV-12, Switched Output
5 120 VAC Switched Output Neutral Line for HV-13, Switched Output
6 3 Way Valve
7 DHW Pump Relay
8 Circ Pump Relay
9 Damper Relay
10 GROUND
11 GROUND
12 120VAC Switched Output 120VAC Output when boiler power is switched ON (pilot duty only)
13 120VAC Switched Output 120VAC Output when boiler power is switched ON (pilot duty only)
14 3 Way Valve
15 DHW Pump Relay
16 Circ Pump Relay
17 Damper Relay
18 Master Alarm Relay
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20 Flame Detected Relay
21
Use of non-factory-authorized replacement parts is not recommended for this
Description
Boiler Supply Power L1, 230 VAC, 1 ph , 60 Hz
Boiler Supply Power L2, 230 VAC, 1 ph , 60 Hz
Boiler Supply Neutral, 0 VAC
Neutral Line for HV-14, 3 Way Valve
Neutral Line for HV-15, DHW Pump Relay
Neutral Line for HV-16, Circ Pump Relay
Neutral Line for HV-17, Damper Relay
Boiler Supply Ground, 0 VAC
Boiler Supply Ground, 0 VAC
120 VAC output during CH Mode, 3 way valve is normally close
(not powered) for DHW mode, and powered open for CH mode.
120 VAC Output when boiler is in DHW mode (pilot duty only)
120 VAC Output when boiler is in CH mode (pilot duty only)
120 VAC Output when boiler is enabled (pilot duty only)
Contacts close when boiler is in alarm state (120/24 VAC at 1 amp
max)
Contacts close when boiler is firing (120/24 VAC at 1 amp max)
MODU-FIRE® Forced Draft Gas-Fired Boiler
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