Unigas R91, Installation Manual

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PART IV: MAINTENANCE
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16 remove the combustion head: to clean it use a vacuum cleaner, scrape off the scale by means of a wire brush;
17 to replace the blast tube from the outside, proceed as follows: unscrew the VB securing dowels and remove the broken blast
tube.to replace the blast tubes from the inside: unscrew the VM securing screws and remove the blast tubes plate; replace the bro-
ken blast tubes.
18 To reassemble, follow the procedure in the reversed order, observing the electrodes measures.
5.4 Electrodes Adjustment
Important Note: Check the ignition and detection electrodes after removing/adjusting the combustion head.
Adjust the electrodes position, according to the quotes shown othe next picture
ATTENTION: while replacing the manifold, remember to insert the “OR”. While centering the heads, do not completely
fasten the manifold screws at its base. Fasten the screws after centering. Do not act on the burner hinge and flange screws.
ATTENTION: avoid the ignition and detection electrodes to contact metallic parts (blast tube, head, etc.), other-
wise the boiler’s operation would be compromised. Check the electrodes position after any intervention on the
combustion head.
VT
T
VP
VM
7
4
8
R525