When installed in the line the vacuum gauge serves to check the vacuum in the suction line of oil heating systems and the degree of contamination of heating oil filters during the oil burner operation
The tee connector is installed just before the oil burner pump, oil lifter, or de-aerator in the suction line
The manometer can be aligned corresponding to the installation direction
Please note: This unit is to be used on the suction side only and is not suitable for use in pressure mode