U.S. Boiler Company MegaSteam MST288, Инструкция по установке, эксплуатации и обслуживанию

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c. Abandoned Openings – Openings through
the chimney wall that are no longer used
shall be sealed in accordance to NFPA 211.
Often abandoned openings are improperly
sealed and usually covered by a gypsum wall
covering.
d. Clean Chimney – Chimney shall be free of all
loose debris.
5. Draft Regulator – the draft regulator supplied with
the boiler (or equivalent) must be used with this
appliance. Refer to Figures 17 and 18.
B. CHIMNEY CONNECTOR
1. A chimney connector (vent pipe) is used to
connect the boiler to the base of the chimney.
The chimney connector should be kept as short
as possible. The horizontal length of the chimney
connector shall not be greater than 10 feet.
NOTE: Secure chimney connector to cast iron
smokebox collar with three (3) #10 x ½" self drilling
hex head TEK screws provided in miscellaneous
parts carton. Locate screws around perimeter
of connector as shown in Figure 18 and
approximately ½" in from edge. Use drill with
5/16" hex bit to drive screws through connector
and smokebox collar.
2. Vent Connector shall be any of the following
and of the same size as the outlet of boiler.
a. Type L or a factory built chimney material
that complies with the Type HT requirements
of ANSI/UL 103. Install in accordance with
listing and manufacturer’s instructions.
b. Steel pipe having resistance to corrosion
and heat with a minimum wall thickness of
24 Gauge (0.024”).
C. DRAFT
1. The natural draft generated through a chimney is
dependent on several factors including, chimney
height, temperature of flue gases, cross section
area of chimney, chimney wall insulation value,
dilution air and total volume of flue gases, to
name a few. Make sure that the boiler has been
running for at least 5 minutes before measuring
the draft.
2. Minimum Draft at Breech (Canopy) – The draft
induced by a chimney must create at least a
pressure of 0 (zero) inches water column (“ w.c.)
at the pressure tapping on the canopy mounted
on rear of boiler (see Figure 19). The pressure
at the canopy cannot be positive since this could
create a condition that allows flue gas by-products
to escape from the draft regulator. A negative
pressure reading up to -.03 inches water column
is acceptable for proper operation. (See Tables
11 thru 11B) Burner Specifications at the rear of
this manual for more details)
3. Minimum Overfire Pressure – The overfire
pressure is another piece of information that is
often measured, however this should be done for
observation purposes only! The breech pressure
must be used to qualify the draft condition. See
Tables 11 thru 11B for more details as a guide.
Actual draft and temperature measurements may
be different then those values in the table.
D. STACK TEMPERATURE
1. The temperature of the flue gases has a significant
effect on the amount of draft created in a vertical
chimney as well as the propensity to create
condensate. The higher the stack temperature,
Figure 19: Smokebox Pressure Tapping for
Checking Draft at Breech
Section V: Venting & Air Intake Piping (continued)
The chimney and connector
shall be inspected annually for signs of debris
and corrosion. Loose mortar at the base of the
chimney may be a sign of condensate damage
to the chimney. A chimney professional shall
be contacted immediately to examine the
damage and recommend a solution. Long
term operation while in this condition may
cause a venting failure and force flue gases
into the living space. If the chimney is to be
re-lined use the recommendations in NFPA 31,
Appendix E or CSA B139.
DANGER
Any signs of condensate
seepage at the base of the chimney shall be
inspected immediately. The discoloration may
be a sign of chimney damage and must be
remedied immediately.
DANGER