19
HARD WATER CONDITIONS
Where hard water conditions exist, water softening or the threshold
type of water treatment is recommended. This will protect the
dishwashers, coffee urns, water heaters, water piping and other
equipment. When water softening or water treatment is not
practical, a comparatively easy method of periodic lime removal
from the unit may be employed.
PRESSURE RELIEF VALVE RATING SHOULD NOT EXCEED
PRESSURE CAPACITY OF ANY COMPONENT IN THE SYSTEM.
INSTALL TEMPERATURE, PRESSURE GAUGE AND PRESSURE
RELIEF AS CLOSE TO BOILER OUTLET AS POSSIBLE.
SHUTOFF VALVES SHOULD BE INSTALLED FOR SERVICING
BOILER, HOWEVER, LOCAL CODES SHALL GOVERN THEIR
USAGE.
THERMAL EXPANSION (CLOSED SYSTEM)
Thermal expansion occurs in any hot water system when system
water is heated or “recovered” during periods of non-use.
If the system is operated in an “open” condition such as being
connected directly to the city main, the volume of expanded water
generated during the recovery periods can be dissipated back
through the “open” connection to the city main so pressure cannot
build up.
However, once a back flow preventer is installed to isolate system
water from the public supply; or a pressure reducing valve is
installed to protect a water meter; or any device preventing flow
back into the cold water supply, the “open” condition becomes
“closed”. During periods of temperature recovery and no usage,
expanded water has no place to go, so the pressure builds up
until a relief valve opens releasing hot water.
A relief valve opening on pressure will flow small amounts of
water, whereas relieving on temperature releases large amounts
of water.
If your system is closed, some provision must be made for
THERMAL EXPANSION to protect the system from excessive
pressure. Install an expansion tank that is properly and adequately
sized for the expanding volume of water in the system.
Service problems or parts failure due to excessive pressure are
NOT
covered under warranty.
TANK PROBE INSTALLATION PROCEDURE
A tank probe system temperature sensor is supplied with each
hot water supply boiler (LW models). When installed on a tank,
the inlet water temperature on the Dia-Scan II will default to the
tank temperature.
See figure 21 and 22 for position of tank
probe jumper. As stated earlier, if one wishes to use an
alternative method of temperature control, this jumper must
be removed.
The tank probe sensor wires are run from the plug on the control
board to the junction box at the rear of the unit. Field wiring (in
conduit) is required from the plug wires to the tank probe sensor wires.
See figure 7.
TANK PROBE SET-POINT ADJUSTMENT
When the temperature sensor is installed in a water tank, and
the sensor is used with the WHC1502 system, the controller will
monitor and control the temperature of the water at the sensor
location. Setting the temperature is accomplished through the
Dia-Scan II control display. The programmable temperature range
is 110°F to 190°F (43°C to 88°C). The switching differential is
fixed at 5°F (3°C).
GAS CONNECTIONS
CAUTION
MAKE SURE THE GAS ON WHICH THE BOILER IS TO OPERATE IS
THE SAME AS THAT SPECIFIED ON THE RATING PLATE. DO NOT
INSTALL THE BOILER IF EQUIPPED FOR A DIFFERENT TYPE OF
GAS. CONSULT YOUR GAS SUPPLIER.
THIS BOILER IS NOT INTENDED TO OPERATE AT GAS SUPPLY
PRESSURE OTHER THAN SHOWN ON THE RATING PLATE. A
LOCK-UP OR POSITIVE SHUT-OFF TYPE REGULATOR MUST BE
INSTALLED IN THE GAS SUPPLY LINE. EXPOSURE TO HIGHER
GAS SUPPLY PRESSURE MAY CAUSE DAMAGE TO GAS VALVES
WHICH CAN RESULT IN FIRE OR EXPLOSION. IF OVERPRESSURE
HAS OCCURRED SUCH AS THROUGH IMPROPER TESTING OF
GAS LINES OR EMERGENCY MALFUNCTION OF THE SUPPLY
SYSTEM, THE GAS VALVES MUST BE CHECKED FOR SAFE
OPERATION. MAKE SURE THAT THE OUTSIDE VENTS ON THE
SUPPLY REGULATORS AND THE SAFETY VENT VALVES ARE
PROTECTED AGAINST BLOCKAGE. THESE ARE PARTS OF THE
GAS SUPPLY SYSTEM, NOT THE BOILER. VENT BLOCKAGE MAY
OCCUR DURING ICE BUILD-UP OR SNOWSTORMS.
THE BOILER MUST BE ISOLATED FROM THE GAS SUPPLY
PIPING SYSTEM BY CLOSING ITS MAIN MANUAL GAS
SHUT-OFF VALVE DURING ANY PRESSURE TESTING OF THE GAS
SUPPLY PIPING SYSTEM AT TEST PRESSURES EQUAL TO OR
LESS THAN 1/2 PSIG.
DISCONNECT THE BOILER AND ITS MAIN MANUAL GAS SHUT-
OFF VALVE FROM THE GAS SUPPLY PIPING DURING ANY
PRESSURE TESTING OF THE GAS SUPPLY SYSTEM OVER
1/2 PSIG. THE GAS SUPPLY LINE MUST BE CAPPED WHEN NOT
CONNECTED TO THE BOILER.
IT IS IMPORTANT TO GUARD AGAINST GAS VALVE FOULING
FROM CONTAMINANTS IN THE GAS WAYS. SUCH FOULING MAY
CAUSE IMPROPER OPERATION, FIRE OR EXPLOSION. IF COPPER
SUPPLY LINES ARE USED THEY MUST BE APPROVED FOR GAS
SERVICE.
WHEN LOCAL CODES REQUIRE A MAIN MANUAL SHUT-OFF
VALVE OUTSIDE THE BOILER JACKET, A SUITABLE MAIN
MANUAL SHUT-OFF VALVE MUST BE INSTALLED IN A LOCATION
COMPLYING WITH THOSE CODES.
BEFORE ATTACHING THE GAS LINE BE SURE THAT ALL GAS
PIPE IS CLEAN ON THE INSIDE.
TO TRAP ANY DIRT OR FOREIGN MATERIAL IN THE GAS
SUPPLY LINE, A DIRT LEG (SOMETIMES CALLED DRIP LEG)
MUST BE INCORPORATED IN THE PIPING. THE DIRT LEG
MUST BE READILY ACCESSIBLE AND NOT SUBJECT TO
FREEZING CONDITIONS. INSTALL IN ACCORDANCE WITH
RECOMMENDATIONS OF SERVING GAS SUPPLIER. REFER TO
NATIONAL FUEL GAS CODE, ANSI Z223.1 OR CAN/CSA – B149.1-
00 (AND LATEST ADDENDA).
Содержание LB 1000
Страница 22: ...22 FIGURE 16 CONNECTION DIAGRAM ...
Страница 23: ...23 FIGURE 17 SCHEMATIC DIAGRAM ...
