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FOR LB/LW-750 AND LB/LW-1000 MODELS:
1. Manually shut off the gas supply by one of the two methods.
On boilers that have a manual shutoff valve downstream from
the automatic gas valves, turn the manual shut off valve to the
“OFF” position. On boilers that do not have the manual shut
off valve located downstream from the automatic valve, the
gas supply must be interrupted at the automatic valves to
perform this check. This may be done by disconnecting the
24 volt lead that supplies the valves. The boiler will shut down
(main burner extinguished) and will try and re-light within 15
seconds. After three (3) ignition attempts (or 1 attempt on
CSD-1 models) the system will lock out. Once lockout has
occurred, check to insure that there is no voltage across the
terminals on the gas control or leading to the gas control in
the case where the lead was disconnected. Return all valves
and wires to their original positions and proceed to Step 2.
2. Shut off the gas supply to the boiler by closing the main manual
gas shut off valve in the gas supply line located outside of the
boiler cabinet. Reset the power to the boiler by turning the
power switch on the boiler to the “OFF” position, wait one (1)
minute and then turn to the “ON” position. If there is sufficient
gas supply pressure to hold the low gas pressure switch
contacts closed, the unit will proceed with the Trial-For-Ignition
and as soon as the gas control opens, the Gas Pressure Fail
Light (red) on the DIA-SCAN II display will come on and the
gas control will close. If the gas supply pressure is low where
the low gas pressure switch contacts remain open, the Gas
Pressure Fail Light (red) on the DIA-SCAN II display will remain
on. The boiler will remain in this state for approximately two
minutes and then proceed to enter lock out mode. Check that
there is no voltage across the gas control terminals before
and after the unit enters the lock out mode. The lock out
message under this condition should be either “Circulation
Fail” or “Inducer Fail” depending upon the state of the switch
when the cycle is initiated.
DANGER
HOT WATER TEMPERATURES REQUIRED FOR AUTOMATIC
DISHWASHER AND LAUNDRY USE CAN CAUSE SCALD
BURNS RESULTING IN SERIOUS PERSONAL INJURY AND/OR
DEATH. THE TEMPERATURE AT WHICH INJURY OCCURS VARIES
WITH THE PERSON'S AGE AND TIME OF EXPOSURE. THE
SLOWER RESPONSE TIME OF CHILDREN, AGED OR DISABLED
PERSONS INCREASES THE HAZARDS TO THEM. NEVER ALLOW
SMALL CHILDREN TO USE A HOT WATER TAP, OR TO DRAW
THEIR OWN BATH WATER. NEVER LEAVE A CHILD OR DISABLED
PERSON UNATTENDED IN A BATHTUB OR SHOWER.
THE WATER HEATER SHOULD BE LOCATED IN AN AREA WHERE
THE GENERAL PUBLIC DOES NOT HAVE ACCESS TO SET
TEMPERATURES.
It is recommended in domestic hot water applications that
lower water temperatures be used to avoid the risk of scalding.
It is further recommended, in all cases, that the water
temperature be set for the lowest temperature which satisfies
the user's hot water needs. This will also provide the most
energy efficient operation of the boiler and minimize scale
formation in the heat exchanger, thus prolonging the life of the
boiler.
SETTING THE WATER HEATER TEMPERATURE AT 120°F (49°C)
WILL REDUCE THE RISK OF SCALDS. Some states require
settings at specific lower temperatures. Table 9 below shows
the approximate time-to-burn relationship for normal adult skin.
TABLE 9. Risk of Scalds
Temperature
Time to Produce 2nd & 3rd
Setting
Degree Burns on Adult Skin
Over 170°F (77°C)
Nearly instantaneous
160°F (71°C)
About 1/2 second
150°F (66°C)
About 1-1/2 seconds
140°F (60°C)
Less than 5 seconds
130°F (54°C)
About 30 seconds
120°F (49°C) or less
More than 5 minutes
Valves for reducing the point-of-use temperatures by mixing cold
and hot water are available. Also available are inexpensive
devices that attach to faucets to limit hot water temperatures.
Contact a licensed plumber or the local plumbing authority.
SHOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL
TO SHUT OFF, TURN OFF THE MAIN MANUAL GAS SHUTOFF
VALVE TO THE APPLIANCE.
WATER TEMPERATURE REGULATION
The operating temperature of the boiler must be maintained as
follows:
• 140°F (60°C) or higher inlet water temperature to the boiler.
• 20°F (11°C) differential between the boiler’s inlet and outlet
(e.g. 140°F [60°C] inlet, 160°F [71°C] outlet minimum design
temperatures).
If the inlet water temperature into the boiler is less than 140°F
(60°C), adjustments on the water bypass and the outlet valves at
the rear of the boiler, figures 13 and 14, are required; wait at least
one minute between adjustments for the temperature to stabilize.
1) If necessary, throttle down (close) the water outlet gate/ball
valve until the desired outlet water temperature (160°F [71°C]
minimum) is reached. Wait one minute.
2) Note the outlet and inlet temperature indicator readings.
a) If the inlet water temperature is less than 140°F (60°C),
open, in small increments, the bypass (balancing) valve
until the minimum 140°F (60°C) inlet water temperature
or 20°F (11°C) differential, whichever has the higher inlet
temperature, is attained.
b) If the inlet water temperature is greater than 140°F (60°C)
and the 20°F (11°C) differential is not present, close the
bypass valve until the 20°F (11°C) differential is attained.
NOTE: It may be necessary to make further adjustments on the
outlet and bypass valves until the desired inlet and outlet water
temperatures are reached.
SEQUENCE OF OPERATION
1. When power is applied to the WHC1502 ignition control, the
Display board will initially run through a self-diagnostic routine,
and then go into its operating mode, displaying the
temperature sensed at the outlet temperature probe.
Содержание LB 1000
Страница 22: ...22 FIGURE 16 CONNECTION DIAGRAM ...
Страница 23: ...23 FIGURE 17 SCHEMATIC DIAGRAM ...
