CAUTION: Should overheating occur or the gas supply fails to shut off, DO NOT turn off or discon- nect the electrical supply to the pump. Instead, shut off the gas supply at a location external to the heater. Failure to observe this precaution may aggravate the overheated condition resulting in possible damage to the heater and injury to the user.
Testing the Ignition Safety Shut-off
The ignition system safety shutoff must be tested by conducting the following tests:
For Standing Pilot Systems
1.With the main burners on, remove the pilot adjust- ment cover screw.
NOTE: There is no pilot adjustment cover on Robertshaw 7200 gas valve.
2.Insert a small slot screw driver and turn the adjust-
ment screw clockwise 
until pilot flame goes out. Count and note number of turns made.
3.Gas valve will shut off main burners after about three (3) minutes. End of test. If the gas valve will not shut off, follow the instructions "To Turn Off Gas To Heater" and call service technician or your gas supplier.
4.Return pilot adjustment screw counterclockwise
same number of turns as in step 2.
3 | 2 | 1 |
|
| PILOT ADJ |
O F F | S E T P I L O T O N | |
PILOT KEY
Pilot Adjustment
Fig. 15: Robertshaw 7200 Gas Valve (Models 0135 &
0195)
5.Replace pilot adjustment cover screw, then follow the lighting instructions to get heater ready for operation.
For Automatic Ignition Systems
1.Turn on power to the ignition systems and turn gas supply off at the gas valve.
2.Check ignition module as follows:
a.Set the tankstat to high setting.
b.Watch for continuous spark at the pilot burner.
c.Time the spark operation. Time must be with- in the lockout timing period (15 or 90 seconds).
d.Turn tankstat down to end call for heat and wait 60 seconds on lockout models before beginning step 3.
3.Turn on gas supply.
4.Set tankstat to high setting.
5.Systems should start as follows:
a.Spark will turn on and pilot gas valve will open at once. Pilot burner should ignite after gas reaches the pilot burner.
b.Spark ignition should cut off when pilot flame is established.
c.Main gas valve should open and main burner should ignite after gas reaches the burner port.
Flame Failure
With burner operating, close the manual fuel valves to simulate a flame failure. System should lock out after safety switch timing (15 seconds). After the safety switch has cooled, open the manual valves (relight standing pilots) and reset the safety switch; the burner should restart.
Inspection Procedures
Burners
Clean main burners and air louvers of dust, lint and debris. Keep heater area clear and free from com- bustibles and flammable liquids. Do not obstruct the flow of combustion and ventilating air. Make visual check of burner and pilot flame. Yellow flame indicates clogging of air openings. Lifting or blowing flame indi- cates excess high gas pressure. Low flame indicates low gas pressure.
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