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ANSI STANDARDS
EXHIBIT A
RECOMMENDED PROCEDURE FOR SAFETY INSPECTION OF AN EXISTING
APPLIANCE INSTALLATION AS A PRELIMINARY STEP TO APPLYING
AN AUTOMATIC INTERMITTENT PILOT SYSTEM
The following procedure is intended as a guide to aid
in determining that an appliance is properly installed and
is in a safe condition for continuing use.
This procedure is predicated on central furnace and
boiler installations equipped with an atmospheric gas
burner(s) and not of the direct vent type. It should be
recognized that generalized test procedures cannot
anticipate all situations. Accordingly, in some cases,
deviation from this procedure may be necessary to
determine safe operation of the equipment.
a. This procedure should be performed prior to any
attempt at modification of the appliance or the instal-
lation.
b. If it is determined there is a condition which could
result in unsafe operation, the appliance should be
shut off and the owner advised of the unsafe condi-
tion.
The following steps should be followed in making the
safety inspection:
1. Conduct a Gas Leakage Test of the appliance
piping and control system downstream of the shutoff
valve in the supply line to the appliance.
2. Visually inspect the venting system for proper size
and horizontal pitch and determine there is no blockage
or restrictions, leakage or corrosion or other deficiencies
which could cause an unsafe condition.
3. Shut off all gas to the appliance and shut off any
other fuel-burning appliance within the same room. Use
the shutoff valve in the shutoff valve in the supply line to
each appliance.
4. Inspect burners and crossovers for blockage and
corrosion.
5. Applicable only to warm air heating appliances.
Inspect heat exchangers for cracks, openings or exces-
sive corrosion.
6. Applicable only to boilers. Inspect for evidence of
water or combustion product leaks.
7. Insofar as is practical, close all building doors and
windows and all doors between the space in which the
appliance is located and other spaces of the building.
Turn on clothes dryers. Turn on any exhaust fans, such
as range hoods and bathroom exhausts, so they will
operate at maximum speed. Do not operate a summer
exhaust fan. Close fireplace dampers. If, after complet-
ing steps 7 through 12, it is believed sufficient combus-
tion air is not available, refer to 1.3.4 of the National Fuel
Gas Code (Z223.1) for guidance.
8. Place in operation the appliance being inspected.
Follow the lighting instructions. Adjust thermostat so
appliance will operate continuously.
9. a. Determine that the pilot is burning properly and
that main burner ignition is satisfactory by inter-
rupting and re-establishing the electrical supply to
the appliance in any convenient manner.
b. Determine manifold pressure in order to match
input after the new control is installed.
a.
Visually determine that main burner gas is burn-
ing properly; i.e., no floating, lifting or flashback.
Adjust the primary air shutter(s) as required.
b.
If appliance is equipped with high and low flame
control or flame modulation, check for proper main
burner operation at low flame.
11. Test for spillage at the draft hood relief opening
after 5 minutes of main burner operation. Use a draft
gauge, the flame of a match or candle, or smoke from a
cigarette, cigar or pipe.
12. Return doors, windows, exhaust fans, fireplace
dampers and all other fuel-burning appliances to their
previous conditions of use.
13. Applicable only to warm air heating appliances.
Check both limit controller and fan controller for proper
operation. Limit controller operation can be checked by
temporarily disconnecting the electrical supply to the
blower motor and determining that the limit control acts
to shut off the main burner gas.
14. Applicable only to boilers:
a. Determine that the circulating water pumps are
in operating condition.
b. Test low water cutoffs, automatic feed con-
trols, pressure and temperature limit controls and
relief valves in accordance with the
manufacturer’s recommendations and instruc-
tions to determine they are in operating condition.
EXHIBIT A OF ANSI STANDARD Z21.71 FOR AUTOMATIC INTERMITTENT PILOT IGNITION SYSTEMS FOR FIELD
INSTALLATION