External Optional Low Water Cut Off - UTICA BOILERS MAHF-100 Manual

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 6-3.
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 6-2, 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 6-3.
• 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.
FIGURE 6-4 - LWCO Wiring Diagram
120 V/60 HZ
L
1
N
G
Conduit or Power
Supply cord
(Polarized)
6 - HYDRONIC PIPING
Electrical Conduit
J-Box
BLK
WHT
GND
33
FIGURE 6-3 - Low Water Cutoff - Detail
NO
NO
YES
Low Water Cutoff (LWCO)
L
1
N
GND
120 V/60 HZ Socket
N.O
(Polarized) 120 V/60 HZ
Cord Set From Boiler
240013371 REV B, [10/01/2021]