8824 Fallbrook Drive
Houston, TX 77064 USA
Phone: 800.444.TEST
Fax: 281.580.0719
Click on the instrument name to reveal the answers to the most frequently asked questions about your instrument.
If your issue isn't addressed here, please feel free to contact our technical support team by clicking on the "Chat Support" button and we will be glad to help you. Help is also available by phone or email; visit the Contact Us page to quickly find the nearest support provider.
Why is the furnace over heating?
Check for a defective Solid State Relay or a shorted Thermocouple and replace as needed.
Why isn't my Thermoelectric Cooler (TEC) cooling?
Check to see the 12VDC is supplied. If so, the temperature sensor or TEC is faulty. If not, check controller and 12VDC power supply.
Why is my furnace only heating to 700-900 degrees?
First, ensure the proper temperature set point. The furnace has two heating elements that work together to maintain the desired temperature. One element alone can only sustain 700-900 degrees for a short period of time before burning out. Verify the integrity of each element by checking the continuity. If an element is burned out (open) the furnace should be replaced.
Why do I have little/no Nitrogen response?
Insure proper sample introduction and combustion. Check for leaks in the sample flow path through the detector and replace/repair as needed. Check for coking/sooting from pyrotube exit through membrane to detector and clean/replace as needed. If you have no response, verify that the ozone detector is on and producing ozone. Check for detector sensitivity by creating a light leak. Pull back one of the rubber light boot coverings and see if the signal shows a significant response. If so continue trouble shooting; if not call technical support.
Why do I have little/no Sulfur response?
Insure proper sample introduction and combustion. Check for leaks in the sample flow path through the detector and replace/repair as needed. Check for coking/sooting from pyrotube exit through membrane to detector and clean/replace as needed. UV lamp may be dead, weak, or turned off.
Why are the Auto Cal Temperatures incorrect?
Contaminated Lead Std or Probe not in center of lead.
Embedded Computer is not running?
Blown Fuse or Defective Computer.
Heater set point cannot be reached
Bus Bar contacts corroded or dirty or Bus-Bar power cable corroded or Heater Power Controller is out of adjustment or Tube shorted to test section.
Why is the watts reading causing the test to abort?
Heater tube not clamped tight in bus bars or Heater tube ID or OD out of tolerance or Heater tube or material not as specified or Heater tube used previously at high temp or Heater tube is shorted to the heater or test section or Improper flow.
Power increases over time
Corrosion build-up on bus bars
Sample fuel flow rate low, erratic, or stopped
Air in lines or Sample Pump needs priming or Fuel clog
What is the difference between a TD-PPA and a GS-PPA?
The TD-PPA can be used for either Diesel or Turbine fuel while a GS-PPA is strictly gasoline.
What can cause my unit to have a problem with flow?
Check to see if the unit is creating pressure in the input bottle and make sure the red fittings are seated properly (careful not to over tighten).
What should I do if I receive a "SOURCE FAULT", "CHOPPER WHEEL ERROR", or "FILTER WHEEL ERROR"?
Contact PAC, the unit should be sent in for inspection.
What should I do if I receive "FUEL LEAK DETECTED, PLEASE POWER DOWN"
Reboot the unit two or three times, make sure the unit is in a well ventilated area. If the unit continues to have the error, check the unit for any fuel leaks or contact PAC.
Can I calibrate my unit onsite?
Yes, but it is highly recommended that the unit be sent to PAC due to the complicity of the calibration, the fuels, the programs needed, and the computers needed. If you would like more details on the calibration procedures, please contact PAC.
Why am I getting a Vapor Pressure Safety Alarm?
Check if boiling stones have been put in the flask. Use only the boiling stones delivered with the apparatus because the dimension is very important. Check if the capillary in the condenser tube of the flask is not clogged. Be sure that the output of the condenser tube is at atmospheric pressure (the beaker at the output should not be sealed). Perform the vapor pressure calibration.
After a few months of use, distillation flasks are covered by a black residue? Does it affect my results?
Yes. The presence of a black residue in the bottom of the distillation flask can damage the accuracy of results especially for products having a FBP ≤ 250°C (FBP - IBP ≤ 25°C). So it is recommended to clean and dry the flasks after each test.
Do I have to adjust the temperature measurement circuit by pure product distillation when the thermocouples have been cleaned?
The frequency of the temperature measurement calibration depends on the user but the accuracy of the vapor and liquid temperature measurement have to be verified at intervals of not more than six months or when thermocouples have been replaced.
At intervals of not more than six months and after one element of the system has been replaced or repaired, verify the accuracy of the liquid and vapor temperature measurement by distilling two pure products:
Caution: Exclusively use pure Toluene and Hexadecane (purity >95% minimum).
After a few months of use, the temperature measurement thermocouples are covered by a black residue, especially the liquid temperature measurement thermocouple. Do I have to clean it ?
It is advised to clean the measuring head and the thermocouples with a tissue paper after each test to remove any trace of residual condensate but it is normal that thermocouples becom black from the first tests. If a residue is accumulated, it must not exceed 0.2mm width (diameter of the liquid thermocouple at the extremity: 2mm)?
If it is the case, call for your local PAC Service Department to dismount thermocouples in order to clean them using an appropriate solvent or to change them.
The cleanliness of the flask and temperature measurement thermocouples (liquid and vapor) directly influences boiling range characteristics so they must be cleaned regulary.
It is preferable to absorb the residue on measuring head thermocouples after each test with a tissue paper removing the condensate of the previous test assuring that the following sample will be not polluted.
Clean the flask after each test. Use an appropriate solvent and dry it. Replace the flask when it is too dirty.
Verify the capillary is not clogged. If it is the case, do not use any tool to unblock it but clean the flask again and use compressed air to dry the flask and unblock the capillary.
When the apparatus is switched on, the LCD screen does not light up.
If the PMD was stored in a cold or wet place, leave the apparatus in a dry and temperate place for 24 hours before switching on. Verify the backlight setting.
Why am I getting no peak response?
Check for a plugged syringe in the autoinjector.
I am showing a loss for the C6 Aromatic number but everything else is ok?
Try changing the inlet septum or check for leaks at the inlet liner.
My total Olefin number is low and my Saturates number is high, Why is this?
You are experiencing Olefin breakthrough of the Olefin trap. You should lower the Olefin adsorption temp and re-inject. If lowering the Olefin trap temp did not help then the Olefin trap may need to be replaced.
My C9 Naphthene and C9 paraffin peaks are broad, sharp and unresolved?
You have moisture on the 13x mol sieve trap, you need to change the external carrier gas filters, condition the 13x mol sieve trap and check for leaks.
I am getting Saturates response but no Aromatics?
Check the incoming valve air pressure to the gc. If there is insufficient air pressure to switch the valves then all peaks will elute in the first 30min of the run. It could also be a broken boiling point capillary column.
