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34
NO
NO
YES
FIGURE 6-5 - Low Water Cutoff - Detail
6 - HYDRONIC PIPING
Low Water Cutoff (LWCO)
Electrical Conduit
J-Box
120 V/60 HZ
Conduit or Power
Supply cord
(Polarized)
L
1
N
G
GND
L
1
N
GND
BLK
WHT
120 V/60 HZ Socket
(Polarized) 120 V/60 HZ
Cord Set From Boiler
N.O
FIGURE 6-4 - LWCO Wiring Diagram
6.6 External Optional Low Water Cut Off
These guidelines are supplied when necessary to install an
additional Low Water Cut Off (LWCO), for sensing a low water
level condition in a boiler, as required by the Authority Having
Jurisdiction.
Follow LWCO manufacturer installation instructions for type of
LWCO selected in addition to these instructions.
LWCO shall be 120V/60HZ control and dry contacts sized for
load being connected. Wire control to boiler. See Figure 6-4.
Connect LWCO device to the system ground. Ground in
accordance with the requirements of the authority having
jurisdiction or, in the absence of such requirements, with the
National Electrical Code (NEC) or Canadian Electrical Code
CEC.
• Locate LWCO sensing device in the supply
piping, above the minimum height of boiler.
See Figure 6-3, Piping Diagram.
• Position control in HORIZONTAL piping to assure proper
boiler protection (upright or 90° rotation).
• For proper operation, sensing element of the LWCO
control shall be positioned in the tee to sense the main
water stream. Maintain minimum 1/4” spacing from pipe
walls. Element shall NOT contact the rear, or side walls of
the tee. See Figure 6-5.
• Install an air vent using a tee to avoid nuisance
shutdowns.
• Apply small amount of pipe sealant to threaded
connections. Use LWCO manufacturer suggested sealant.
• Arrange piping to prevent water dripping onto boiler.
•
DO NOT install water shutoff valve between boiler and
LWCO sensing device.
240013354 REV B [09/15/2021]
Summary of Contents for MAC-115
Page 2: ...MAC 205 ...
Page 4: ...MAH 165 ...
Page 77: ...73 APPENDIX A WIRING DIAGRAMS A 2 MODEL 125 Heat Only 240013354 REV B 09 15 2021 ...
Page 78: ...74 APPENDIX A WIRING DIAGRAMS A 3 MODEL 165 Heat Only 240013354 REV B 09 15 2021 ...
Page 79: ...75 APPENDIX A WIRING DIAGRAMS A 1 MODEL 115 Combi 240013354 REV B 09 15 2021 ...
Page 80: ...76 APPENDIX A WIRING DIAGRAMS A 4 MODEL 150 Combi 240013354 REV B 09 15 2021 ...
Page 81: ...77 APPENDIX A WIRING DIAGRAMS A 5 MODEL 205 Combi 240013354 REV B 09 15 2021 ...
Page 82: ...78 NOTES 240013354 REV B 09 15 2021 ...
Page 118: ...34 MODEL 125 Heat Only 125 HEAT ONLY WIRING DIAGRAM PN 240011430 REV P 09 15 2021 ...
Page 119: ...35 MODEL 165 Heat Only 165 HEAT ONLY WIRING DIAGRAM PN 240011430 REV P 09 15 2021 ...
Page 120: ...36 115 COMBI WIRING DIAGRAM MODEL 115 Combi PN 240011430 REV P 09 15 2021 ...
Page 121: ...37 MODEL 150 Combi 150 COMBI WIRING DIAGRAM PN 240011430 REV P 09 15 2021 ...
Page 122: ...38 MODEL 205 Combi 205 COMBI WIRING DIAGRAM PN 240011430 REV P 09 15 2021 ...
Page 127: ...43 Low Water Cutoff Detail LOW WATER CUTOFF NO NO YES PN 240011430 REV P 09 15 2021 ...
Page 132: ...48 3 FAULT SOLUTION SECTIONS PN 240011430 REV P 09 15 2021 ...