41
TABLE 18.
WATER HARDNESS MEDIUM (0-12 GRAINS PER GALLON)
XW MODEL
NO.
∆T ºF
GPM
∆P FEET
1000
25
76
17.5
1300
25
99
22
1700
25
129
23
2000
25
152
17.5
2600
25
198
22
3400
25
258
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 setpoint should not exceed 140 ºF.
Note: The factory installed/supplied pump on the above listed
model boilers is sized to maintian a 25 ºF
∆T
through the boiler
when the boiler 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 of
equivalent feet of piping between the boiler and a storage tank.
All piping between the boiler and the storage tank must be of
a pipe size equal to the inlet/outlets of the boiler. 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.
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 operation to avoid flue gas emission from the condensate
drain line. Failure to fill the trap could result in severe personal
injury or death.
HOT WATER CAN SCALD:
Boilers are intended to produce hot
water. Water heated to a temperature which will satisfy space
heating, clothes washing, dish washing and other sanitizing
needs can scald and permanently injure you upon contact.
Some people are more likely to be permanently injured by hot
water than others. These include the elderly, children, the infirm
or physically/mentally disabled. If anyone using hot water in your
home fits into one of theses groups or if there is a local code or
state law requiring a specific temperature water at the hot water
tap, then you must take special precautions. In addition to using
the lowest possible temperature setting that satisfies your hot
water needs, a means such as a mixing valve should be used
at the hot water taps used by these people or at the hot water
supply tank. Mixing valves are available at plumbing supply
or hardware stores. Follow the manufacturer’s instructions for
installation of the valves. Before changing the thermostat setting
on the hot water system controller, refer to Table 17.
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 boiler should be located in an area that is inaccessible to the
general public.
TABLE 17. RISK OF SCALDS
Water Temperature
Time to Produce 2nd & 3rd
Degree Burns on Adult Skin
180°F (82°C)
Nearly instantaneous
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)
More than 5 minutes
Should overheating occur or the gas supply fail to shut off, turn
off the main manual gas shutoff valve to the boiler.
CHECK/CONTROL WATER HARDNESS
XW Model XP Boilers 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. Refer to Table 18 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.
