The interior and exterior of the instrument should be kept clean and free of lint and other accumulations. Nozzles and Test Plates should be kept in individual containers and cleaned only with compressed Air or as directed by Frazier Co. They should be protected from dirt and scratches. Under normal conditions the only parts of the instrument subject to wear are the motor-blower and the variable transformer. Since these are constructed of heavy duty components, it is to be expected that they should last 20 years or more. From time to time the clamping screws may also be stripped, but they are easily recognizable and repairable.
Over a period of about 3 years or so, the red oil may deteriorate and should be changed for fresh oil. The best indication of this condition is the fading of bright red color. In actual practice this condition may never develop due to the necessity of removing the oil from the manometers in order to remove spilled oil from the copper tubes of the vacuum system as below.
In actual usage about 95% of the time when incorrect readings are obtained by the instrument, they are usually due to the oil being driven into the copper tubes of the vacuum system due to careless use of the instrument or operation by an inexperienced person. Incorrect readings may also result from a damaged, corroded or dirty orifice in the nozzles. A test plate is provided as a convenient check of the operating condition of the instrument. However, this test plate may also change its calibration over time due to dirt accumulation or wear.
To obtain correct readings, the following procedure should be followed if the instrument is not operating properly:
1. Check the nozzles for obvious damage such as nicks or scratches, corrosion or dirt. Check the Test Plate to see if the holes are obstructed by as much as a single fiber. (The Test Plate should only be cleaned with compressed air.) Run the instrument with the Test Plate again and check. If still not correct proceed as below after disconnecting electrical source.
2. Remove the oil from the reservoirs.
3. Disconnect and remove the copper tubes from under the table by cutting the rubber connectors. Note: The rubber connectors are assembled by using a minute amount of a dilute solution of soap & water as a lubricant. This solution acts as a glue when dry. Care must be taken not to break the glass tubes or bend the copper tubes when disconnecting.)
4. Cut open the rubber connectors and check to see if oil has passed through them. (The surface will be shinny with oil where the copper tubes do not butt exactly.) This will indicate if there is some oil residue below the connection.
5. Run a small amount of Acetone (not mineral spirits or alcohol) through the copper tubes and blow out with compressed air. Repeat this procedure for added insurance.
6. Run some Acetone through and blow out the connectors to the large double chamber under the table. Poke a pipe cleaner or similar tool into the connectors from both sides to eliminate any semi-solid obstruction (such as spider webs, lint etc.). Repeat the procedure.
7. Reconnect all tubes and fill reservoir with oil until the oil reaches the "O" mark on the scale. (The Low Pressure Inclined Manometer will slowly change oil level over several hours and should be readjusted with fine tuning knob on the upper right hand cover of the manometer.) Check with the Test Plate to see if the instrument is now operating properly.
8. If the instrument is not operating properly, repeat steps 2 through 6.
9. Remove the inclined manometer from the backboard and rinse with Acetone until it runs out clear. Be sure to run Acetone out of point where the copper tubes attach to the inclined manometer. Blow out with compressed air. Repeat the procedure. Then reconnect.
10. If the instrument is still not operating properly check the whole system for air leaks or flattened tubes.
11. If still not operating properly, contact Frazier Co. for advice and a check of the Test Plate and Nozzles. Do not attempt to adjust the instrument in order to calibrate it. You cannot recalibrate the instrument yourself. Recalibration can only be effected by Frazier Co. Almost any adjustment you can make will cause the instrument to permanently malfunction.
12. If all else fails consider returning the instrument to Frazier Co. for repair and/or recalibration.