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.