Weil-McLain GOLD CGt Manual page 41

GOLD CGt Gas-Fired Water Boiler — Boiler Manual
(continued)
❏
Check/test . . . . . . .
Expansion tank
1. Expansion tanks provide space for water to move in
and out as the heating system water expands due to
temperature increase or contracts as the water cools.
Tanks may be open, closed or diaphragm or bladder
type. See section
suggested best location of expansion tanks and air
eliminators.
— located above highest radiator or
Open-type
baseboard unit, usually in the attic or closet. Has a
gauge glass and overflow pipe to a drain.
— welded gas tight and located above
Closed-type
boiler. Tank is partially filled with water, leaving an
air cushion for expansion.
• Make sure this type of tank is fitted with a
, such as the B & G Tank-Trol or Taco
fitting
Taco-Trol. This fitting 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.
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
a rubber membrane to separate the tank pressurizing
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
preferably located on top of an air eliminator,
as shown in examples in manual section
pages 21-27.
2. If relief valve has tended to weep frequently, the
expansion tank may be waterlogged or undersized.
Closed-type tank
Install a tank fitting if not already installed. Then check
fill level per fitting manufacturer's instructions. If fill
level is correct, check tank size against manufacturer's
instructions. Replace with a larger tank if necessary.
Diaphragm- or bladder-type
to be sure it is large enough for the system. If size is
too small, add additional tank(s) as necessary to
provide sufficient expansion. If tank size is large
enough, remove tank from system and check charge
pressure (usually 12 psig for residential applications).
If tank won't hold pressure, membrane has been
damaged. Replace tank.
Part Number 550-110-290/0501
, pages 21-27 of this manual, for
4
The air will escape
— welded gas tight with
,
automatic air vent
4
— tank is most likely waterlogged.
— first, check tank size
Boiler relief valve
tank
Figure 32
Relief valve,
typical
,
071037
1. Inspect the relief valve and lift the lever to verify flow as
in the following warnings, excerpted from a relief valve
manufacturer's warning label. Before operating any relief
valve, ensure that it is piped with its discharge in a safe
area to avoid severe scald potential. Read manual section
, page 20, before proceeding further.
4
2. After following the above warning directions, if the relief
valve weeps or will not seat properly, replace the relief valve.
Ensure that the reason for relief valve weeping is the valve
and not over-pressurization of the system due to
expansion tank waterlogging or undersizing.
Safety relief valves should be
AT LEAST ONCE EVERY THREE YEARS
a licensed plumbing contractor or
authorized inspection agency, to ensure
that the product has not been affected by
corrosive water conditions and to ensure
that the valve and discharge line have not
been altered or tampered with illegally.
Certain naturally occurring conditions
may corrode the valve or its components
over time, rendering the valve inoperative.
Such conditions are not detectable unless
the valve and its components are physically
removed and inspected. This inspection
must only be conducted by a plumbing
contractor or authorized inspection agency
— not by the owner. Failure to reinspect
the boiler relief valve as directed could
result in unsafe pressure buildup, which
can result in severe personal injury, death
or substantial property damage.
Following installation, the
valve lever must
be operated AT LEAST ONCE A YEAR
ensure that waterways are clear. Certain
naturally occurring mineral deposits may
adhere to the valve, rendering it
inoperative. When manually operating the
lever, water will discharge and precautions
must be taken to avoid contact with hot
water and to avoid water damage. Before
operating lever, check to see that a
discharge line is connected to this valve
directing the flow of hot water from the
valve to a proper place of disposal
otherwise severe personal injury may
result.
If no water flows, valve is
Shut down boiler until a new
inoperative.
relief valve has been installed.
reinspected
, by
to
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