PCA 25 Configuration and Operation*
* This information is provided in addition to the manual included with the instrument and not to be considered all inclusive. Do read the manual. To download a copy of the Operator's Manual in Adobe Reader (a pdf file) click here.
Before turning the instrument on, the hose and probe assembly must be attached. If the thermocouple is not plugged in you will get a t-couple error after the 60 second warm up period.
On the bottom of the instrument you will see two thermocouple outlets and three additional ports. The larger (combustion gas) fitting goes on the left hand side (labeled 'gas'), the smaller fitting goes on the right hand side (labeled 'draft').
Note: PCA 25's manufactured since approximately January of 2001 have two 'draft' ports to enable the instrument to be used to measure External Static Pressure (ESP) and airflow. If your instrument was manufactured before that date, a retrofit kit is available. Contact Bacharach customer service (800-736-4666) or a service center for information on the upgrade.
To obtain stack temperature readings, plug the yellow thermocouple plug into the yellow port on the left hand side labeled 'T-Stack'. The thermocouple port on the right hand side labeled 'T-Air' is for an auxiliary thermocouple. This is normally used when testing a "sealed" combustion unit which pulls combustion air from the outside.
Remember, the Steady State Efficiency (SSE) calculation is determined by the net stack temperature. If an auxiliary thermocouple is not plugged in, there is a thermocouple inside the case of the instrument. This makes the assumption that the temperature of the instrument is approximately the same as the combustion air temperature.
You will notice that the right spade plug is slightly larger than the left one and corresponds with the slightly larger connection on the outlet. You may want to put a mark on the topside of the plug to make it easier to determine which way the plug goes in. In the above photo, an 'X' indicates which side of the thermocouple is up.
Note: you may want to consider purchasing two auxiliary thermocouples to use the instrument when measuring temperature rise or any other delta T measurements.
You are now ready to turn the instrument on. To do this, press the ON/OFF button in the lower right hand corner below the display.
Warning: do not place the probe in the sample location until after the instrument has gone through the 60 second warm up period. Doing so will not damage the instrument but will result in meaningless test results.
Immediately after pressing the On/OFF button, the display will begin a 60 second countdown during the warm up period.
Once the 60 second 'warm up' period is complete, the screen will appear in the 'hold' mode and should look like this:
In the upper right hand corner of the display, you will see the letters 'HLD' (Hold). To begin sampling, press the RUN button. The letters 'RUN' should appear and you will hear the pump operating.
Keep in mind that unless flue gases are being sampled, several of the screens in the display will show dashes where the readings should be. Until the O2 reading gets below 15%, the instrument will not make a number of calculations.
Warning: Should the instrument display read 'CO Sensor Error' after the 60 second warm up period, this means one of two things:
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The Carbon Monoxide sensor needs replacing or |
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The instrument has been turned on in an environment contaminated with carbon monoxide and the operator may be in danger of Carbon Monoxide exposure. |
This instrument performs what is termed an 'automatic calibration' during the warm up period and will calibrate to 0 ppm's CO unless the levels are in excess of approximately 80ppm's. In the event that the ambient air has in excess of approximately 80 ppm's CO, the display will read 'CO Sensor Error' to warn the operator that they may be in danger of exposure.
Should this occur, vacate the area and attempt to turn the instrument on outside in clean air. Should the instrument again display the error message, the sensor needs replacing. If it calibrates down successfully, re-enter the building while watching the CO reading to see if carbon monoxide is present and take any appropriate actions.
This instrument can be used for CO source investigations, just remember to turn it on outside in clean air (not near a busy intersection, for example).
Before using the instrument, it must be configured for fuel type as well as unit of measurement for temperature/pressure and date/time.
To set this up, press the MENU button.
Fuel Type Selection
Pressing the MENU button once will first bring up the 'fuel type' screen.
Press the Scroll Up/Down buttons to select the type of fuel being tested.
Once the cursor is next to the proper fuel type, press the ENTER* button.
*Note: You must press the ENTER button to save your selection.
Zeroing the Pressure Sensor
Pressing the Menu button a second time will bring you to the screen which zero's the draft reading.
The display will prompt you to disconnect the draft hose* and press ENTER.
*Note: It is also acceptable to remove the probe from the stack instead of disconnecting the draft hose from the instrument.
The display will then prompt you to reconnect the draft hose (or return the probe to the sampling location).
Should the reading be anything but 0, repeat the procedure.
Note: You will also see the term 'HOT SPOT' in the display. In some parts of the world, flue gas samples are required to be taken from the area with the highest stack temperatures.
Memory Directory
Pressing the MENU button a third time will bring you to the memory where test results can be saved. More on that later.
Temperature Unit Selection
Pressing the MENU button a fourth time will bring you to the screen where the unit of temperature measurement is selected. Press the Scroll Up/Down buttons to select either Fahrenheit (F) or Centigrade (C).
Make your selection and be sure to press ENTER * to save your selection.
*Note: You must press the ENTER button to save your selection.
Pressure Unit Selection
Pressing the MENU button a fifth time will allow you to select the unit of measurement for the pressure readings.
Press the Scroll Up/Down buttons to select millibars (MB), Pascals (PA) or water column inches (WC) and press ENTER * to save the unit of measurement.
*Note: You must press the ENTER button to save your selection.
Language Selection
Pressing the MENU button a sixth time will allow the language in the display to be selected.
Again, press the Scroll Up/Down buttons to set the cursor to the desired language and press ENTER *.
*Note: You must press the ENTER button to save your selection.
Date/Time Selection
Pressing the Scroll Up/Down button a seventh time will access the TIME/DATE screen.
Press the Scroll Up/Down button to select either the time or date to be changed, then press ENTER. Repeatedly pressing the ENTER button will move the cursor over the numbers. Pressing the Scroll Up/Down buttons will change the number. Press the ENTER button to make your selection and move on to the next digit.
Calibration Mode
Pressing the MENU button an eighth time will access the calibration screen.
Caution: Entering the password and accessing the calibration set up should only be done by trained, qualified personnel. Playing around with this by someone who doesn't know what they are doing may result in readings out of calibration.
We suggest that calibration of the PCA be done by a service center. This instrument has a hydrogen compensated CO sensor which requires the use of two cylinders of calibration gas and is a bit more complicated to perform an accurate CO sensor calibration.
Should you desire to do calibrations yourself, get in touch with us for further information.
Also, keep in mind that when a PCA is sent in for calibration, the pressure and temperature sensors are calibrated as well.
Exiting the Configuration Screens
Pressing the RUN button during any of the setup screens will return the instrument to the combustion screen in the 'hold' mode.
Press the RUN button again to activate the pump and begin sampling.
Saving Test Results
To save a particular set of test results, press the ENTER button while the cursor is next to the 'S' in the lower right hand corner of the display.
The display will indicate which memory location the test results are being saved to for later retrieval.
Once the tenth memory location is filled, new saved information overwrites previous readings starting at the first memory location.
Printing Test Results
To print out the test results, place the printer approximately 18" in front of the IR transmitter on top of the instrument. Press the Scroll Up button so the cursor is next to the 'P' and press ENTER. After a slight delay, the printer should start printing the test results. Leave the instrument and printer in the same location until the print process is completed.
Retrieving Test Results from the Memory
To retrieve and/or print test results saved to memory, press the MENU button three times to bring up the memory directory.
Press the Scroll Up/Down buttons to select the test results to be retrieved and press ENTER. The selected test results should then appear in the display. To print that set of results, press the Scroll Up button so the cursor is next to the 'P' and press ENTER.
Turning the Instrument Off
To shut the instrument down, simply press the ON/OFF button.
The display will count down for 5 seconds and the instrument will turn off.
Should you accidentally hit the ON/OFF button and want to continue using the instrument, press the RUN button before the 5 seconds are up and the instrument will resume operation.
For information regarding electronic test instrument maintenance go to Instrument Maintenance Tips.
Find out more about where to test and what results you should expect see, go to Application Information.
For information about interpreting test results and troubleshooting, go to Combustion Test Interpretation.