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7. Make sure that the detector is sighting the flame
properly.
8. If necessary, resight or reposition the flame detector.
If proper operation cannot be obtained, replace the flame
detector and/or the R7795.
INITIAL LIGHTOFF CHECK FOR PROVED
PILOT (All Installations Using a Pilot)
Perform this check on all installations using a pilot. It
should immediately follow the preliminary inspection.
NOTE: Low fuel pressure limits, if used, could be open. If
so, bypass them with jumpers during this check.
1. Open the master switch.
2. Make sure the manual main fuel shutoff valve(s) is
closed. Open the manual pilot shutoff valve. (If the pilot
takeoff is downstream from the manual main fuel shutoff
valve, make sure the main fuel is shut off just upstream
from the burner inlet, or disconnect the power from the
automatic main fuel valve(s).)
3. Close the master switch and start the system with a
call for heat (raise the setpoint of the burner controller).
4. Let the sequence advance through the prepurge.
During the ignition trial period, spark should occur and the
pilot should light. If ignition occurs, proceed to step 7.
5. If the pilot flame is not established in ten seconds
(four seconds if the orange jumper is clipped), safety shut-
down will occur. Let the sequence complete its cycle.
6. Reset the lockout switch and let the system recycle
once. If the pilot still fails to ignite, make the following
ignition/pilot adjustments:
a. Open the master switch and remove the R7795
from the subbase.
b. Jumper subbase terminal L1 to the ignition termi-
nal 18.
c. Close the master switch. This energizes only the
ignition transformer.
d. If the ignition spark is not strong and contin-
uous, open the master switch and adjust the
ignition electrode spark gap to the manufacturer
recommendation.
e. Make sure the ignition electrodes are clean.
f. Close the master switch and observe the spark.
g. Once a continuous spark is obtained, open the
master switch and add a jumper from L1 to the
pilot terminal 5.
h. Close the master switch. This energizes both the
pilot valve and ignition transformer.
i. If the pilot does not ignite with continuous spark,
adjust the pilot gas pressure regulator until a pilot
is established.
j. Open the master switch, remove the jumpers, and
reinstall the R7795 onto the subbase. Close the
master switch and let the system recycle.
7. When the pilot ignites, measure the flame signal. If
necessary, adjust the flame or detector to give the proper
flame signal.
8. Recycle the system to recheck lightoff and the pilot
flame signal.
NOTE: The next steps require two people—one to open
the manual main shutoff valve(s) and one to watch for
ignition.
9. When entering the main flame ignition trial period,
make sure that the automatic main fuel valve(s) are open;
then smoothly open the manual main fuel shutoff valve
(and manually opened safety shutoff valve, if used) and
watch for main burner flame ignition. If the main burner
flame is not established within five seconds (or the time
specified by the burner manufacturer), close the manual
main fuel shutoff valve(s), open the master switch and
continue with step 10. If the main burner flame is estab-
lished, proceed to step 13.
10. Wait about three minutes, close the master switch,
and let the R7795 recycle to the main flame ignition trial
period. Smoothly open the manual main fuel shutoff valve(s)
and try lightoff again. The first attempt may have been
necessary to purge the fuel lines and bring sufficient fuel
to the burner.
11. If the main burner still does not light off within five
seconds (or the time specified by the burner manufacturer),
close the manual main fuel shutoff valve(s) and open the
master switch. Check all burner adjustments.
12. Repeat steps 10 through 12 until the main flame
establishes properly; then go on to step 13.
13. When the main flame is established, the sequence
will stay in run. Make burner adjustments for flame stabil-
ity and input rating.
14. Shut down the system by lowering the setpoint of
the controller. Make sure that:
• the main burner flame goes out.
• the intermittent pilot (if used) goes out.
• all automatic fuel valves close.
15. If used, remove the bypass jumpers from the low fuel
pressure limit.
16. Restart the system by raising the controller setpoint.
Observe that the pilot is established during the trial for pilot
flame period within the normal lightoff time specified by
the burner manufacturer.
17. Measure the flame signal. Continue to check for the
proper signal (Table 3) through the run period.
18. Run the burner through another sequence, observing
the flame signal for:
• pilot alone (if applicable).
• pilot and main burner.
• main burner flame alone (unless monitoring an
intermittent pilot).
Also observe the main flame lightoff time.
19. Make sure that all readings are in the required ranges
before proceeding.
13
R7795A,B,C,D
CHECKOUT
66-2001—2
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