A.O. Smith 100 Series, Руководство по обслуживанию

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Servicing should only be performed by a Qualified Service Agent
CHECK/CONTROL WATER HARDNESS
XWH water heaters are approved for use in Domestic Water Heating Systems with a water supply hardness of 0 grains per gallon to a
maximim of 12 grains per gallon and a Total Dissolved Solids (TDS) not exceeding 350 PPM. Heating water having higher grains/TDS
specified here requires larger circulating pump. Consult manufacturer when heating water exceeding these specs. Refer to Table 6
for recommend flow rate to maintain scale free operation with up to a medium water hardness. For scale free operation in hard water
systems with a water hardness greater than 12 grains per gallon, a water softener must be installed and maintained.
XW MODEL
NO.
∆T ºF GPM (LPM) ∆P FEET
1000 25 76 (287.6) 17.5
1300 25 99 (374.7) 22
1700 25 129 (488.2) 23
2000 25 152 (575.3) 17.5
2600 25 198 (749.4) 22
3400 25 258 (976.53) 23
∆T ºF = Temperature rise ºF at the specified GPM.
GPM = Flow rate in gallons per minute.
∆P = Pressure loss through the heat exchanger in feet of head.
For systems over 5 grains per gallon; and for scale free operation, boiler/water heater setpoint should not exceed 140 ºF.
Note: The factory installed/supplied pump on the above listed models of boilers/water heaters is sized to maintian a 25 ºF
∆T
through the boiler/water heater when the boiler/water heater is firing at 100% fire.
In addtion to the pressure loss through the heat exchanger, the factory supplied pump is sized for an additional 50 feet (15.2 m)
of equivalent feet of piping between the boiler/water heater and a storage tank. All piping between the boiler/water heater and the
storage tank must be of a pipe size equal to the inlet/outlet(s) of the boiler/water heater. Installation differences may slightly change
these parameters.
FREEZE PROTECTION (HYDRONIC HEATING INSTALLATION)
1. Determine freeze protection fluid quantity using system water content, following fluid manufacturer’s instructions.
2. Local codes may require a backflow preventer or actual disconnect from city water supply.
3. When using freeze protection fluid with automatic fill, install a water meter to monitor water makeup. Freeze protection fluid may
leak before the water begins to leak, causing concentration to drop, reducing the freeze protection level.
INSPECT/FILL CONDENSATE SYSTEM
Inspect/check condensate lines and fittings:
1. Inspect the condensate drain line, condensate PVC fittings and condensate trap. Repair any leaks.
Fill condensate trap with water:
1. Remove the 2 inch PVC cap with the switch located at the top of the trap.
2. Fill with fresh water until the water begins to pour out of the drain.
3. Replace the cap. Press the cap onto the trap until the cap makes contact with the drain.
The condensate trap must be filled with water during all times of boiler/water heater operation to avoid flue gas emission from the
condensate drain line. Failure to fill the trap could result in severe personal injury or death.
TABLE 6. WATER HARDNESS MEDIUM (0-12 GRAINS PER GALLON)