Teledyne GFC-7001T - Trace CO Analyzer - Manual (Page 247)

MaintenanceTeledyne API – Model T300/T300M CO Analyzer
Teledyne Analytical Instruments 247
11.3.2. PERFORMING LEAK CHECKS
Leaks are the most common cause of analyzer malfunction; Section Error! Reference
source not found. presents a simple leak check procedure. Section 11.3.2.1 details a
more thorough procedure.
11.3.2.1. PRESSURE LEAK CHECK
Obtain a leak checker similar to the TAI P/N 01960, which contains a small pump, shut-
off valve and pressure gauge. Alternatively, a convenient source of low-pressure gas is
a tank of span gas, with the two-stage regulator adjusted to less than 15 psi with a
shutoff valve and pressure gauge.
CAUTION
G
ENERAL
S
AFETY
H
AZARD
Do not use bubble solution with vacuum applied to the analyzer. The solution may
contaminate the instrument. Do not exceed 15 PSIG pressure.
1. Turn OFF power to the instrument.
2. Install a leak checker or tank of gas as described above on the sample inlet at the
rear panel.
3. Remove the instrument cover and the flow assembly and plug it with the
appropriate gas-tight fitting.
4. Pressurize the instrument with the leak checker, allowing enough time to fully
pressurize the instrument through the critical flow orifice. Check each fitting with
soap bubble solution, looking for bubbles. Once the fittings have been wetted with
soap solution, do not re-apply vacuum, as it will suck soap solution into the
instrument and contaminate it. Do not exceed 15 psi pressure.
5. If the instrument has one of the zero and span valve options, the normally closed
ports on each valve should also be separately checked. Connect the leak checker to
the normally closed ports and check with soap bubble solution.
6. Once the leak has been located and repaired, the leak-down rate should be < 1 in-Hg
(0.4 psi) in 5 minutes after the pressure is shut off.
11.3.3. PERFORMING A SAMPLE FLOW CHECK
CAUTION
G ENERAL S AFETY H AZARD
Always use a separate calibrated flow meter capable of measuring flows in the 0 – 1000
cm 3 /min range to measure the gas flow rate though the analyzer.
DO NOT use the built in flow measurement viewable from the Front Panel of the
instrument. This measurement is only for detecting major flow interruptions such as
clogged or plugged gas lines.
See Figure 3-4 for SAMPLE port location.
1. Attach the Flow Meter to the sample inlet port on the rear panel. Ensure that the
inlet to the Flow Meter is at atmospheric pressure.
2. Sample flow should be 800 cm 3 /min  10%.