Should you own a combustion analyzer?
My kids jokingly call me cheap, as I do not like to spend money. When analyzing a purchase, I equate it to how many hours I must work on a lousy jobsite to pay for my indulgence.
One of the most cost-effective sales/service tools I have is a combustion analyzer. It has paid for itself many times over, as I use it for all types of HVAC equipment and not just boilers. It can generate thousands of dollars of extra revenue yearly and verify the safety of your customer’s systems. The combustion analyzer can read and display the efficiency and emissions of any fuel fired appliance. The analyzer will also read and display the carbon monoxide levels.
If you service boilers, a combustion analyzer is almost a must-have tool. Some techs tell me they can eyeball the flame and adjust the air-to-fuel ratio. Even after four decades in the trade, I have never been able to do that. What looks like a good flame could be spewing thousands of parts per million of dangerous carbon monoxide out the flue. I like using a before- and after-adjustment readout and show it to the customer, explaining how I made the unit safer or more efficient.
One of the ways the combustion analyzer could pay for itself is to use it on every heating service call that includes boilers, packaged rooftop units, furnaces, pool heaters, water heaters and even ovens.
A manufacturer’s representative who sells combustion analyzers told me he urges contractors to use an analyzer on every call and charge a small fee for the use. He calls it an emission test fee and further suggests you give a printout of the readings to the customer with the service report.
The analyzer can even be used to check the heat exchanger of forced-air furnaces. A cracked heat exchanger can change air-to-fuel readings when the blower starts. In a pinch, I have used it to test for carbon monoxide leaks inside a home or building.
Costs for an analyzer range from several hundred to several thousand dollars, depending on the options and gases you want to measure. If you service large commercial or industrial boilers, you may be at the top end of the price curve. These more expensive models typically will allow you to measure NOx and SOx, thought to be a cause of greenhouse gases and acid rain.
If you invest in an analyzer, it should be calibrated regularly to be sure the readings are correct — typically every year or two. Some must be returned to the manufacturer for the testing and calibration. The calibration time may be extended if you wait until fall, when the factory is busy. A few manufacturers allow you to replace your sensors with factory-calibrated ones to limit downtime and maintenance costs. In addition, the analyzer should not be left inside a service vehicle during cold weather, as low temperatures could damage the unit.
We received a call from a residential customer one evening saying his carbon monoxide alarm was sounding. He thought it could be caused by the furnace we installed a few months earlier. We used our combustion analyzer and found the cause of the carbon monoxide was the oven and not our furnace. The customer was baking cookies and something spilled inside the oven. Since ovens are not vented to a chimney or outside, you would be amazed or scared at the carbon monoxide readings from a dirty oven.
Many analyzers will allow you to measure the draft in the stack or chimney. The draft is a measurement of the flue gas velocity through the boiler. If the velocity is too high, the boiler efficiency drops because the unit cannot transfer heat from the flame to the boiler. If the draft is too low, it could create a dangerous condition and possible damage to the boiler and burner.
One of the benefits of using a combustion analyzer is the printer. If you purchase an analyzer, I recommend you get one with a printer. It allows you to document your findings and protect your company. I like to print a copy of the readings and keep it on the jobsite for future reference. I also make a copy and include it in the customer file at the office.
I had a customer tell me something happened to his boiler and it sooted about a month after we visited, and he tried to blame us. I checked the new readings and compared them to the ones from the previous visit and they were much different. The owner had asbestos removed from the pipes and the workers stepped all over the burner and linkages, changing the readings.
I was hired to consult on a problem boiler project in another city and brought my analyzer with me as a carry-on on the airplane. While going through security, I was asked what was in my carry-on. I proudly said, “It’s a combustion analyzer.” That must have been a trigger word and I was escorted by two large security men with no sense of humor to a room and they questioned me. I had to start the unit and demonstrate how it worked. They were impressed and allowed me to return to the line and I barely made the flight. On the return trip, the security asked me what was in my carry-on bag. I learned my lesson and said, “It’s a boiler efficiency tester.” They let me walk through without detaining me.
I urge you to consider a combustion analyzer for your company. It will separate you from the other companies in our highly competitive industry.