GWA
Gas-Fired Water Boilers –
Boiler Manual
13
Part Number 670 01 1001 00
Table 5
Pipe capacity for 0.60 specific gravity natural gas
4
Install gas piping
Natural Gas:
1. See Table 5 for pipe length and diameter. Base on rated
boiler input (divide by 1,000 to obtain cubic feet per hour).
Table 5 is only for gas with specific gravity 0.60, with a
pressure drop through the gas piping of 0.30" w.c. For
additional gas pipe sizing information, see ANSI Z223.1
(B149.1 or B149.2 for Canadian installations).
2. Inlet pressure required at gas valve inlet:
•
Maximum: 13" w.c.
•
Minimum: 5" w.c.
•
Manifold gas pressure: 3.5" w.c.
3. Install 100% lockup gas pressure regulator in supply line if
inlet pressure exceeds 13" w.c. Adjust for 13" w.c. maximum.
Propane Gas:
1. Contact gas supplier to size pipes, tanks and 100% lockup
gas pressure regulator.
2. Adjust propane supply regulator provided by gas supplier
for 13" w.c. maximum pressure.
3. Inlet pressure required at gas valve inlet:
•
Maximum: 13" w.c.
•
Minimum: 11" w.c.
•
Manifold gas pressure: 10" w.c.
Gas pipe
length
(feet)
Capacity of pipe for pipe size of:
(
Capacity in standard cubic feet gas per hour
)
½"
¾"
1"
1¼"
1½"
10
132
278
520
1050
1600
20
92
190
350
730
1100
30
73
152
285
590
860
40
63
130
245
500
760
50
56
115
215
440
670
75
45
93
175
360
545
100
38
79
150
305
460
150
31
64
120
250
380
1. Remove jacket front panel and see Figure 10 to pipe gas to
boiler.
a. Install drip leg at inlet of gas connection to boiler. Where
local utility requires drip leg to be extended to the floor, use
appropriate length of nipple between cap and tee.
b.
Install ground joint union for servicing, when required.
c. Install manual shutoff valve in gas supply piping outside
boiler jacket when required by local codes or utility
requirements.
d. In Canada — When using manual main shutoff valve, it must
be identified by the installer.
2. Support piping with hangers, not by boiler or its accessories.
3. Purge all air from gas supply piping.
4. Before placing boiler in operation, check boiler and its gas
connection for leaks.
a. Close manual main shutoff valve during any pressure
testing at less than 13" w.c.
b.
Disconnect boiler and gas valve from gas supply piping
during any pressure testing greater than 13" w.c.
Do not check for gas leaks with an open flame —
Use bubble test. Failure to use bubble test or check
for gas leaks can cause severe personal injury, death
or substantial property damage.
5. Use pipe dope compatible with propane gases. Apply sparingly
only to male threads of pipe joints so that pipe dope does not
block gas flow.
Failure to apply pipe dope as described in this manual
can result in severe personal injury, death or
substantial property damage.
Connecting gas supply piping to boiler
Figure 10
Gas supply piping
GWA
Gas-Fired Water Boilers –
Boiler Manual
24
Part Number 670 01 1001 00
The boiler should be inspected and started annually,
at the beginning of the heating season, only by a
qualified service technician. In addition, the
maintenance and care of the boiler designated in
Table 6, page 22 and explained on the following pages
must be performed to assure maximum boiler
efficiency and reliability. Failure to service and
maintain the boiler and system could result in
equipment failure.
Electrical shock hazard — Turn off power to the boiler
before any service operation on the boiler except as
noted otherwise in this manual. Failure to turn off
electrical power could result in electrical shock,
causing severe personal injury or death.
The boiler contains ceramic fiber and fiberglass
materials. Use care when handling these materials
per instructions on page 23 of this manual. Failure to
comply could result in severe personal injury.
❏
❏
❏
❏
❏
Inspect . . . . . . . . . .
Reported problems
Inspect any problems reported by owner and correct before
proceeding.
Boiler area
1. Verify that boiler area is free of any combustible materials,
gasoline and other flammable vapors and liquids.
2. Verify that boiler area (and air intake) is free of any of the
contaminants listed in Table 2 on page 5 of this manual. If any of
these are present in the boiler intake air vicinity, they must be
removed. If they cannot be removed, install combustion air piping
to the boiler in accordance with national, provincial or local
codes.
Air openings
1. Verify that combustion and ventilation air openings 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 gas vent system
1. Visually inspect entire flue gas venting system for blockage,
deterioration or leakage. Repair any joints that show signs of
leakage in accordance with vent manufacturer’s instructions.
2. Verify that masonry chimneys are lined, lining is in good
condition, and there are not openings into the chimney.
Failure to inspect for the above conditions and have
them repaired can result in severe personal injury or
death.
Pilot and main burner flames
1. Visually inspect pilot burner and main burner flames as directed
under Section 6, page 17 of this manual.
10 Service and maintenance
continued
Water piping
1. Check the boiler interior piping and all system piping for signs
of leaks.
2. Repair any leaks before proceeding.
Do not use petroleum-based cleaning or sealing
compounds in boiler system. Severe damage to boiler
will occur, resulting in substantial property damage.
Eliminate all system or boiler leaks. Continual fresh
makeup water will reduce boiler life. Minerals can
build up in sections, reducing heat transfer,
overheating cast iron, and causing section failure.
Leaking water may also cause severe property
damage.
❏
❏
❏
❏
❏
Inspect . . . . . . . . . .
Boiler heating surfaces
1. Disconnect the vent pipe at the boiler draft hood and remove
draft hood after turning off power to the boiler.
2. Use a bright light to inspect the boiler flue collector and heating
surfaces.
3. If the vent pipe or boiler interior surfaces show evidence of
soot, follow “Cleaning boiler heating surfaces” in this manual
section, page 26. Remove the flue collector and clean the boiler
if necessary after closer inspection of boiler heating surfaces.
4. If there is evidence of rusty scale deposits on boiler surfaces,
check the water piping and control system to make sure the
boiler return water temperature is properly maintained (per this
manual).
5. Reconnect vent and draft hood. Replace all boiler components
before returning to service.
6. Check inside and around boiler for evidence of any leaks from
the boiler. If found, locate source of leaks and repair.
Burners and base
1. After turning off power to the boiler, remove the jacket door and
base access panel (Figure 17, item 4, page 30).
2. Inspect burners and all other components in the boiler base.
3. If burners must be cleaned, raise rear of each burner to release
from support slot, slide forward and remove. Then brush and
vacuum the burners thoroughly, making sure all ports are free
of debris. Carefully replace all burners, making sure burner with
pilot bracket is replaced in its original position and all burners
are upright (ports up).
4. Inspect the base insulation.
The boiler contains ceramic fiber and fiberglass
materials. Use care when handling these materials
per instructions on page 23 of this manual. Failure to
comply could result in severe personal injury.
a. Verify that the insulation is intact and secure against all four
sides of the base.
If insulation is damaged or displaced, do not operate
the boiler. Replace or reposition insulation as
necessary. Failure to replace damaged insulation can
result in a fire hazard, causing severe personal injury,
death or substantial property damage.
