Series Premier VS-VH
Page 62
LT135 Dec 2019
If the Vacuum is too low, inspect the Flexible Boot Connectors on the Inlet and Outlet of the Vacuum Pump
for tight connections, leaks, damage, kinks, etc.
To adjust the vacuum on a single leg, manipulate the damper coupling at the end of that leg.
To adjust the vacuum on the entire system, manipulate the damper coupling at the vacuum pump.
4. There should be no sound of leaking air around any of the various gaskets or connections.
Burner adjustment
1. Observe each flame through the flame sight glass.
Flame may flutter once or twice at ignition but should settle promptly.
Flame should extend straight out from Ignitor
Sense rod (and ignitor) will glow bright red/orange.
2. End burners (No. 1, or the furthest upstream from vacuum pump) do not need to be adjusted. The flame in a
No. 1 burner, it is solid blue in colour.
3. All downstream burners (Nos. 2 - 4) may require adjustment of the Maxitrol regulator located inside each VS
burner; refer to Burner Adjustment under Commissioning Chapter.
4. VS-VH systems with multiple in-series burners can occasionally produce a high-pitched noise that can be best
be described as a whistle, or howl. Usually the howl is produced by a rich no. 2 burner. De-tune the burner by
slowly reducing the gas pressure at the internal Maxitrol regulator in the burner. You may also have to de-tune
the no. 3 burner. Tum down the pressure till the noise disappears. Reducing it too much may cause ignition
problems later.
