Testing the ignition safety shut-off, Safe shut-down tests, For standing pilot systems – Raypak RAYTHERM 0135B User Manual

Page 30: Limit action, Flame failure

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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.

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.

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.

3

2

1

S

E

T

P

I

L

O

T

O

N

O

F

F

PIL

O

T

AD

J

PILOT KEY

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).

Pilot Adjustment

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

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

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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