Product Overview

BluVac+ LTE User’s Guide
12
Frequently Asked Questions
Q. How often must I calibrate the BluVac+ LTE?
A. Calibration of the BluVac+ LTE is only necessary when the Calibration Test indicates that
calibration is required. Regardless, frequent cleaning and/or calibration will not adversely affect the
long-term reliability of the instrument. For best results, ensure the sensor is clean and dry, and the
dust cap is in place, prior to calibration.
Q. Can I use the BluVac+ LTE to check the proper operation of my vacuum pump?
A. Yes. Attach the BluVac+ directly to the pump with a short hose or coupler. Turn the pump on,
open the blank-off valve, and close the ballast. A good pump with clean and dry oil will typically pull
very quickly to less than 100 microns (generally around 25 microns for a two-stage pump). Always
close the blank-off valve and/or disconnect the BluVac+ prior to turning off the pump so as to avoid oil
contamination of the sensor.
Q. The BluVac+ LTE does not indicate acceptably low pressure when I test my pump.
A. Ensure the pump oil is clean and dry (it should be completely clear when viewed through the
pump’s sight glass). Replace the oil. Ensure the pump ballast is completely closed and the blank-off
valve is completely open, and all fittings are tight and seals are not damaged. If low pressure is still
not achieved, the pump may be damaged or worn.
Q. I’ve attached the BluVac+ LTE directly to my pump with a short hose or coupler. As soon as I
blank off the pump, the indicated pressure rises rapidly. Is sensor leaking?
A. No. There will always be molecular-sized leaks, outgassing, and/or permeation in any hose or
fitting, and the pump’s blank-off valve may not be entirely gas tight. The indicated pressure will rise
due to the small internal volume of the hose or coupler.
Q. What is the recommended method for attaching the BluVac+ LTE for evacuation service?
A. Ideally, the BluVac+ LTE should be as close to the internals of the system under evacuation, and
as far from the vacuum pump as possible. Attaching the BluVac+ LTE to the auxiliary port of a
vacuum-rated core removal tool (CRT) connected directly to a service port is the best method. The
ball-valve of the CRT can be closed to completely isolate the system from the pump and hoses,
thereby allowing for an accurate rise-time test at the completion of evacuation. Additionally, removing
the Schrader core(s) via the CRT and using large diameter hoses will greatly speed the evacuation
process.
Q. I accidentally exposed the BluVac+ LTE to high-pressure refrigerant. Did I damage the BluVac+
LTE?
A. No. The BluVac+ LTE sensor is rated to 500 PSI overpressure, and can be directly exposed to
gas/liquid refrigerant. At worst, the sensor may be exposed to oil, in which case the oil indicator will
activate and cleaning/calibration may be required.