ECR International Utica Boilers UB95M-200, Installation Manual

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sense flame during operation. The DSI is a durable,
reliable component that resists breakage due to
handling or inadvertent impact with other objects.
MANUAL RESET LOW WATER CUT OFF
This appliance employs a factory installed integral
low water cut off (LWCO) that has to be manually
reset if there is a low water condition. The LWCO
senses water through a probe at the top of the boiler
that sends a signal through the water to ground. If the
signal is not sensed through the ground, the LWCO
enters a lockout mode that disables the appliance.
If the LWCO is in normal mode a red indicator light
is illuminated on the LWCO panel in the boiler. Dur-
ing a low water condition, the red light goes out and
the LWCO and control reset buttons on the display
panel must be depressed to reset the LWCO.
NORMALLY CLOSED LWCO SWITCH
This switch is normally closed and spring loaded so
that, when depressed, it opens, and closes again
when pressure is removed. The switch is used as
the manual reset for the LWCO. When tripped the
LWCO will remain in lockout until the water level
reaches the probe and the switch is depressed to
an open state and then released to a closed state,
which sends a signal to the LWCO to resume nor-
mal operation. The boiler control reset button must
then be pressed to reset from a low water condi-
tion. The LWCO switch and control reset button are
located on the display panel of the boiler.
HIGH LIMIT AQUASTAT CONTROL
The high limit aquastat control is a redundant safety
limit control that determines the maximum boiler wa-
ter temperature and also provides a means for pro-
tecting the boiler and heating system from unsafe
operating conditions which could damage the boiler.
The aquastat is mounted in the ½” NPT control well
and ¾” x ½” bushing on the top of the front boiler
section at the hot water outlet. The aquastat is tied
in with the boiler control and is factory set at 200°F
water temperature. The high limit setpoint is field ad-
justable and may be set anywhere between 100°F
and 200°F, with the maximum high limit setpoint not
exceeding 200°F. The field high limit setpoint ad-
justment for each installation depends on heating
system requirements. The aquastat automatically
resets when the boiler water temperature decreases
ten degrees below the high limit setpoint value.
NOTE: Boiler operating temperature (temperature curve) is
calculated and set in the parameters of the boiler control.
CASTING TEMPERATURE SAFETY SWITCH
In the event of lack of or loss of water in the boiler,
the casting temperature safety switch (230°F set-
point) installed on the top of the aluminum boil-
er section behind the supply piping shuts off the
boiler by shutting off power to the boiler control
and causes a failure code to be displayed on the
digital readout. This fault requires manual reset of
the casting temperature safety switch to restart the
boiler and the reset to be pressed on the user in-
terface panel. Verify that the boiler is properly filled
with water before resetting this switch.
WARNING
Never run cold water into a hot, empty boiler.
CIRCULATOR PUMP
Every forced hot water system requires at least one
circulating pump. The circulating pump imparts the
necessary energy to move water through the closed
loop supply and return piping systems, terminal
heating equipment (finned tube radiators, etc.) and
back through the boiler for reheating. To provide the
required hot water flow rates, the circulator pump
must be properly sized to overcome frictional losses
(usually measured in feet of water, also referred to
as “pump head loss”) of the supply and return piping
systems and boiler. The circulator pump is furnished
in a carton within the boiler cabinet. The circulator(s)
should always be located on the downstream
(“pumping away”) side of the expansion tank.
AIR PROVING BLOCKED VENT
SAFETY ASSEMBLY
The air proving blocked vent safety assembly incor-
porates two pressure switches that are wired in se-
ries to discontinue operation of the appliance if there
is a problem with the blower or venting system. The
normally open switch closes upon the initiation of the
blower and functions as an air proving switch. The