®
Series 3
WATER
BOILER
— Boiler Manual
Check all piping for leaks
Eliminate all system or boiler leaks. Con-
tinual fresh make-up water will reduce
boiler life. Minerals can build up in sec-
tions, reducing heat transfer, overheat-
ing heat exchanger, and causing heat
exchanger failure. Leaking water may also
cause severe property damage.
1. Inspect all water and oil piping and verify to be leak
free.
2. Look for signs of leaking lines and correct any prob-
lems found.
3. Check fuel lines and fuel unit as recommended in
fuel unit and burner manuals.
Check air openings
1. Verify that combustion and ventilation air open-
ings to the boiler room and/or building are open
and unobstructed. Check operation and wiring of
automatic combustion air dampers, if used.
2. Verify that boiler vent discharge and air intake are
clean and free of obstructions.
Flue vent system and air piping
Visually inspect entire fl ue gas venting system (and
air piping, if installed) for blockage, deterioration or
leakage. Repair any joints that show signs of leakage
in accordance with vent manufacturer’s instructions.
When air is ducted to burner, verify that air inlet piping
is connected and properly sealed.
Failure to inspect for the above condi-
tions and have them repaired can result
in severe personal injury or death.
Check water system
1. Verify all system components are correctly installed
and operational.
2. Check the cold fi ll pressure for the system. Verify it
is correct (usually around 12 psig).
3. Watch the system pressure as the boiler heats up
(during testing) to ensure pressure doesn’t rise too
high. Excessive pressure rise indicates expansion
tank sizing or performance problem.
4. Inspect automatic air vents and air separators.
Remove air vent caps and briefl y press push valve
to fl ush vent. Replace caps. Make sure vents do not
leak. Replace any leaking vents.
Check expansion tank
General guidelines
Expansion tanks provide space for water to move in and
out as the heating system water expands due to tempera-
ture increase or contracts as the water cools. Tanks may
be open, closed or diaphragm or bladder type. Follow
guidelines in this manual for the best location of the
expansion tank.
Open-type
— located above highest radiator or
baseboard unit, usually in the attic or closet. Has a
gauge glass and overfl ow pipe to a drain.
Closed-type
— welded gas tight and located above
boiler. Tank is partially fi lled with water, leaving an
air cushion for expansion.
• Make sure this type of tank is fi tted with a tank fi tting,
such as the B & G Tank-Trol or Taco Taco-Trol. This
fi tting reduces gravity circulation of air-saturated tank
water back to the system and prevents the air from
bubbling up through the water as it returns from the
system.
• Do not use automatic air vents in systems with closed-
type tanks. The air will escape from the system instead
of returning to the tank. Eventually, the tank will
waterlog and no longer control pressurization. The
boiler relief valve will weep frequently.
Diaphragm or bladder-type
— welded gas tight
with a rubber membrane to separate the tank pres-
surizing air and the water. May be located at any
point in the system, but most often found near the
boiler.
• Systems with this type of expansion tank require at least
one automatic air vent, preferably located on top of an
air eliminator, as shown in the example on page 15.
Troubleshooting a weeping relief valve
If relief valve has tended to weep frequently, the expan-
sion tank may be waterlogged or undersized.
Closed-type tank
— tank is most likely water-
logged. Install a tank fi tting if not already installed.
Then check fill level per fitting manufacturer’s
instructions. If fi ll level is correct, check tank size
against manufacturer’s instructions. Replace with
a larger tank if necessary.
Diaphragm or bladder-type
— fi rst, check tank
size to be sure it is large enough for the system. If
size is too small, add additional tank(s) as neces-
sary to provide suffi cient expansion. If tank size is
large enough, remove tank from system and check
charge pressure (usually 12 psig for residential ap-
plications). If tank won’t hold pressure, membrane
has been damaged. Replace tank.
Annual service and start-up
(continued)
Part number 550-142-182/1014
27