External Optional Low Water Cut Off - UTICA BOILERS MAHF-75 Installation, Operation And Maintenance Manual

6.6 External Optional Low Water Cut Off

These guidelines are supplied when necessary t o inst all
an additional Low Water Cut Off (LWCO), for sensing a
low wat er level condit ion in a boiler, as required by t he
Aut horit y Having Jurisdict ion.
Follow LWCO m anufact urer inst allat ion inst ruct ions for
t ype of LWCO select ed in addit ion t o t hese inst ruct ions.
LWCO shall be 120V/ 60HZ cont rol and dry cont act s
sized for load being connect ed. Wire cont rol t o boiler.
See Figure 6- 3.
Connect LWCO device t o t he syst em ground. Ground
in accordance wit h t he requirem ent s of t he aut horit y
having j urisdict ion or, in t he absence of such
requirem ent s, wit h t he Nat ional Elect rical Code ( NEC) or
Canadian Elect rical Code CEC.
• Locat e LWCO sensing device in t he supply
piping, above t he m inim um height of boiler.
See Figure 6- 2, Piping Diagram .
• Posit ion cont rol in HORI ZONTAL piping t o assure
proper boiler prot ect ion ( upright or 90° rot at ion) .
• For proper operat ion, sensing elem ent of t he LWCO
cont rol shall be posit ioned in t he t ee t o sense t he
m ain wat er st ream . Maint ain m inim um 1/ 4" spacing
from pipe walls. Elem ent shall NOT cont act t he rear,
or side walls of t he t ee. See Figure 6- 3.
• I nst all an air vent using a t ee t o avoid nuisance
shut downs.
• Apply sm all am ount of pipe sealant t o t hreaded
connect ions. Use LWCO m anufact urer suggest ed
sealant .
• Arrange piping t o prevent wat er dripping ont o boiler.
• DO NOT install water shutoff valve between boiler
and LWCO sensing device.
FI GURE 6 - 4 - LW CO W iring Dia gra m
120 V/ 60 HZ
L
1
N
G
Conduit or Power
Supply cord
( Polarized)
6 - H YD RON I C PI PI N G
Elect rical Conduit
J- Box
BLK
WHT
GND
3 5
FIGURE 6-3 - Low Water Cutoff - Detail
N O
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
240013503 REV A, [ 03/ 15/ 2022]