Roberts Gorden UltraVac NEMA 4 - Manual (Page 36)

ROBERTS GORDON ® ULTRAVAC™ C ONTROLLER I NSTALLATION M ANUAL
30
FIGURE 20: End Vent Vacuum
6
5
4
3
2
1
0
1
2
3
4
5
6
Manometer
Insert tubing
about 6" (15cm)
into end vent.
Combustion Chamber
at end burner position
End Vent
Approximate reading after adjusting
VFD frequency setting and/or
damper couplings. ( 2.5"-3" wc) ~~