CleaverBrooks CBEX Elite, Эксплуатация и обслуживание

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750-368
CBEX Elite 100-1200 HP 5-7
5.6 — Firing Preparations for Gas (Series 200-700)
•
If the burner is a combination fuel model, set the gas/oil switch to
“gas.” Withdraw the oil burner gun and latch it in its rearward (lockout)
position.
•
On initial startup, it is recommended that the main gas shutoff cock
remains closed until the programmer has cycled through pre-purge and
pilot sequences. When the fuel light on the control panel comes on,
observe the action of the motorized gas valve stem to determine that it
opens when energized.
FIGURE 5-5.
Oil Gun in the Lock-Out Position
As soon as it is confirmed, turn the burner switch “off” and let the programmer finish its cycle. Check that the
gas valve has closed. Again, turn the burner “on.” When the fuel valve light glows, slowly open the main gas
cock. Main flame should ignite unless there is air present in the line. If the flame is not established within about
5 seconds, turn the burner switch “off” and allow the programmer to recycle normally for a new lighting trial.
Several efforts may be necessary to “bleed” air from the line.
Once the main flame is established, turn the burner
switch to the “off” position and observe that the
flame is extinguished promptly. The flame may con-
tinue to burn for a second or two after normal shut-
down due to the gas remaining downstream from the
fuel valve. If the flame continues to burn for a longer
period or during blower motor spindown, it could
indicate a main gas valve leak. Immediately turn the
burner switch “off” and close the main gas cock.
Investigate and correct the cause of the valve leakage
before relighting the burner.
FIGURE 5-6.
Gas Train and Shutoff Cock
The main gas valve should provide a tight seal, if nothing prevents tight closure. Foreign material may be present
in either the new or renovated gas lines unless adequate care is taken in cleaning and purging.
When the conditions covered above in Section 5.1 - 5.6 are assured, the burner is ready for firing.
Do not repeat unsuccessful lighting attempts without re-checking the burner and pilot adjustments. Failure to follow
these instructions could result in serious injury or death.
NOTE: The burner and control system are designed to provide a pre-purge period of fan operation prior to establish-
ing ignition spark and pilot flame. Do not attempt to circumvent this feature.
! Warning