Smith Cast Iron Boilers Series 28A - Manual (Page 22)

Page 22 SERIES 28A BOILER INSTALLATION AND OPERATION INSTRUCTIONS
Water Boilers
Fill the boiler and all of the radiation with water to the
required system pressure. Completely purge the system
of air and adjust the system pressure as needed.
CAUTION: Thermal shock of water boilers must be
avoided! Water circulation must be established
before the burner is fired. If hot standby is required,
special piping and operation procedures are
necessary, consult your Smith representative.
Failure to protect the boiler from thermal shock can
damage the boiler, voiding the warranty!
Steam Boilers
Fill the boiler with water to the normal water level line
of 50 1/2 in.,
1.28 m from the floor.
If the boiler is connected to a hot steam line, keep the
cold boiler valved off line and fire the burner until the
boiler pressure exceeds the system pressure by 1 to 2
psig,
7 to 14 kPa. Slowly open the main isolation valve
on the boiler to bring it on line.
CAUTION: Never place a cold boiler into service on
a hot steam line or severe damage to the boiler and
piping can occur voiding the warranty!
Steam entering a cold boiler will cool quickly and can
cause severe steam hammer and boiler flooding. Idle
boilers not valved off from the system should have an
overflow installed to prevent it from being flooded.
If an overflow trap is not installed per Figure 24, and
the boiler becomes flooded, the flooded boiler must be
heated to a near steaming condition, 210
°
F, 99
°
C, then
drained to the correct water level.
Water and Steam Boilers
Follow the burner manufactures lighting instructions that
were supplied with the burner.
WARNING: Never attempt to start the burner if
the combustion chamber contains excess oil or
gas, when the boiler is full of vapor or the
combustion chamber is very hot. Failure to
comply with this warning can result in an
explosion causing extensive property damage,
severe personal injury or death!
A properly adjusted gas burner on high fire will produce
a CO
2
of 8.5 to 9.5% with a CO level under 300 ppm.
When firing on oil at high fire, the burner should be
adjusted to produce a CO
2
of 11.0 to 12.0% with a zero
smoke. The flue gas samples should be taken at the
smoke hood. Confirm proper burner adjustment with a
calibrated combustion analyzer.
WARNING: Never use an open flame to test for
gas leaks. Always use an approved leak
detection method. Failure to comply with this
warning can cause extensive property damage,
severe personal injury or death!
Whenever the gas supply piping is pressure tested the
boiler gas controls must be protected. If the test
pressure is equal to, or less than 1/2 psig,
3.5 kPa,
isolate the boiler by closing the manual shut off valve
in the gas supply pipe to the boiler. If the test pressure
is greater than, or equal to 1/2 psig,
3.5 kPa, disconnect
the boiler and its individual shut-off valve from the gas
supply.
ELECTRICAL WIRING
Electrical Power Connections
CAUTION: Label all wires prior to disconnection
when servicing controls. Wiring errors can cause
improper and dangerous operation! Verify proper
operation after servicing.
The electrical connections to this boiler must be made
in accordance with all applicable local codes and the
latest revision of the National Electrical Code, ANSI/
NFPA-70. Installation should also conform with CSA
C22.1 Canadian Electrical Code Part I if installed in
Canada. Install a separate circuit properly rated for the
boiler. A shut-off switch should be located at the boiler.
The boiler must be grounded in accordance with the
authority having jurisdiction, or if none, the latest revision
of the National Electrical Code, ANSI/NFPA-70.
Line voltage field wiring of any controls or other devices
must conform to the temperature limitation of type T wire
at 95
°
F, 35
°
C above room temperature. Use copper
conductors with a minimum size of #14 awg.
BOILER OPERATION
WARNING: Before proceeding read and fully
understand the instructions contained in this
manual. Do not attempt to operate this boiler if
it has not been installed in accordance with the
guidelines set forth in this manual. Failure to
comply with this warning can result in extensive
property damage, severe personal injury or
death!
CAUTION: The supply temperature of a boiler set for
a 20
°
F, 11
°
C temperature rise must not be below
140
°
F, 60
°
C for an oil boiler, 149
°
F, 65
°
C for a gas
boiler. Failure to protect the boiler from low return
water temperatures will damage the boiler, voiding
the warranty!