With the concerns of green house gases and global warning, it is imperative to be able to properly measure the particulates and pollutants being released into the atmosphere. Combustion boilers release a variety of gases while operating, although these exact gases may vary depending on what type of fuel is being burnt. Most countries have regulations on the gas output of these boilers. The EPA has required that testing is performed on gases like H2S, SO2, NO2, and NO. These testing parameters and methods may sometimes require a certificate in order to show that your boiler is under the regulation.
You can take the gas reading of your own boiler by using a thermocouple and portable electrochemical analyzer. Thermocouples are not very difficult to obtain and can be found at most boiler stores. This probe can help to record and measure the temperature towards the flue’s base.
Find an area on the combi boiler stack where you want to perform your test. Select a spot with two stack diameter downstream away from any restrictions, expansions, or any other flow disturbances. Drill a hole in the selected area, this hole should be about the same size as your electrochemical analyzer probe. Insert the EC probe into the hole, but try to make sure that no flue gases escape while you are working.
For 5 minutes, take a gas reading every 30 seconds throughout the ramp up phase. Record your gas sample readings, along with the sample temperature and flow rate. Take the flue gas readings again for 2 minutes every 15 seconds during the test data phase period. Again, record all of your readings and samples. Use the second phase to help calculate the estimated concentration of each gas level tested.
The final phase is known as the refresh phase. You should take records every eight minutes during this time. You could also follow the instructions on the EC that should specify when the boiler is ‘refreshed’. Record all the readings and then analyze them with the emission requirements in your area.
