Smith Cast Iron Boilers Series 28A - Manual (Page 21)

Page 21 SERIES 28A BOILER INSTALLATION AND OPERATION INSTRUCTIONS
Install 3" nipples and ball valves in the two 3" NPT front
section tappings so the boiler can be blown down.
The feed water requirements for steam boilers at full
input are shown in Table 9. The addition of water to the
boiler should be controlled by sensing the actual boiler
water level. 1" NPT water column tappings are provided
on the front section for the mounting of the required
water level controls, see Figure 17.
CAUTION: Makeup water connections must be made
to the return piping and not to the boiler or the
boiler may be damaged voiding the warranty!
Cleaning of Steam Boilers
The burner must be installed and made operational
along with the operating, limit and other safety controls.
The burner on oil boilers must be adjusted to prevent
sooting of the boiler flues. Final burner adjustment
should be made after the boiler has been properly
cleaned.
CAUTION: Failure to properly clean the boiler can
result in foaming and surging and prevent proper
operation of the boiler! Boiler damage can occur
voiding the warranty!
NOTE: Do not connect the boiler to the return piping
until the system piping has been thoroughly flushed
or recontamination of the boiler can occur.
1. Plug the 4" NPT return tappings in the back section
and any other unused tappings, see step 5 below.
WARNING: The safety valve must be installed
and piped to the floor to prevent scalding in the
event of a discharge, see Figure 15. The
discharge piping must be sized the same as the
safety valve outlet. Never install any type of
valve between the boiler and the safety valve!
Failure to comply with this warning can result
in an explosion causing extensive property
damage, severe personal injury or death!
2. Fill the boiler with water to a level 1 in., 25.4 mm
below the normal water level line of 50 1/2 in.,
1.28 m from the floor.
3. Pipe a skimmer off the 6" NPT tapping in the front
section using 1 1/2" NPT pipe.
4. Make a cleaning solution by mixing 1 lb, 0.45 kg
each off caustic soda and trisodium phosphate for
every 50 ga,
189 L of water, see Table 7.
CAUTION: Avoid skin contact with cleaning solution
to prevent injury! If eye or skin contact occurs flush
with large quantities of water.
NOTE: Some locations do not allow this solution to
be used. Check with the local authority having
jurisdiction.
5. Mix the cleaning chemicals with water to create a
concentrated solution. Pour the cleaning solution
through one of the top tappings in the front section
and plug it.
6. Immediately fire the boiler and maintain a steam
pressure of 0 to 2 psig,
0 to 13.8 kPa. It may be
necessary to cycle the boiler.
WARNING: Monitor the boiler pressure
constantly during the cleaning procedure. Do
not allow the boiler pressure to exceed 15 PSI,
103 kPa or a discharge of hot water and steam
will occur!
7. Adjust the water feed to prevent the build up of
pressure within the boiler. Continue the skimming
process until the discharge runs clear.
8. Shut the boiler off and allow the boiler to cool to
100
°
F, 34
°
C. Remove the skim piping and plug the
tapping. Open the blowdown valve and flush the
boiler until the discharge runs clear.
9. Close the blowdown valve and fill the boiler with
water to a level 1in.,
25 mm below the normal water
level line.
10. Check the traps and vents for proper operation.
BURNER INSTALLATION
WARNING: The burner must be installed in
accordance with the burner manufactures
instructions. Check the boiler rating plate to
make sure that the boiler is for the type of fuel
that will be used. If it isn’t, do not connect the
burner to the fuel supply. Failure to comply with
this warning can result in extensive property
damage, severe personal injury or death!
Follow the burner manufacturer’s installation instructions
for the proper installation, fuel piping, wiring, burner
adjustment and servicing. Mount the burner per the
instructions on page 13.
When applicable, provisions for vent, bleed and gas
relief lines must be made in accordance with the latest
revision of ANSI Z223.1/NFPA 54.