Raypak 0180B Type H manual Testing the Ignition Safety Shut-off, Safe Shut-down Tests

3.Turn off all gas valves supplying gas to the boiler. Refer to operating instruction label on the boiler.

4.Shut-off the water supply to the boiler piping sys- tem loop.

5.Open drain valve on the boiler to remove water from the boiler and the piping circuits.

NOTE: It may be necessary to open the purge valves and/ or manual air vents to facilitate complete drainage of water from the heating system.

CAUTION: Should overheating occur or the gas supply fails to shut-off, DO NOT turn off or disconnect the electrical supply to the pump. Instead, shut-off the gas supply at a location external to the boiler. Failure to observe this precaution may aggravate the overheated condition resulting in possible damage to the boiler and injury to the user.

Testing the Ignition Safety Shut-off

The ignition system safety shut-off 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

adjustment screw clockwise until pilot flame goes out. Note and count number of turns made.

3.Gas valve will shut-off main burners after about three (3) minutes. If the gas valve will not shut-off, follow the instructions "To Turn Off Gas To Boiler" and call service technician or your gas supplier.

4.Return pilot adjustment screw counter-clock-

wise , using the same number of turns as in step (b).

e.Replace pilot adjustment cover screw, then follow the lighting instructions to get boiler ready for operation.

For Automatic Ignition Systems Intermittent Ignition (IID)

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 thermostat or controller above room temperature to call for heat.

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 thermostat down to end call for heat and wait 60 seconds on lockout models before beginning step 3.

3.Turn on gas supply.

4.Set thermostat or controller above room tempera- ture to call for heat.

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.

Safe Shut-down Tests

Limit Action

With the burner operating, lower the high limit setting to simulate an overheated boiler. Normal shutdown should occur. Restore the normal limit setting, and the burner should restart.

Flame Failure

3	2	1
		PILOT ADJ
O F F	S E T P I L O T O N

Pilot Adjustment

Fig. 32: Robertshaw 7200 Gas Valve (Models 90, 135, 180)

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 burn- er should restart.

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