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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