What to do – and what not to do – with your Flue Gas Analyser/Combustion Analyzer

A durable, accurate and versatile flue gas analyser/combustion analyzer is a wonderful thing. For many heating and gas engineers, it’s tough to get a day’s work done without one. That’s why it makes sense to treat your analyser well – and in this blog post we’ll be giving you some tips on how to do just that. 

How to keep your analyser happy 

  • The most important rule of all is this: get your flue gas analyser/gas combustion analyzer calibrated every year, on time, without fail. No excuses! 
  • If you can, book your analyser in for service or recalibration at the time you need it least (for example, if you are going on holiday or planning some time off). 
  • Keep an eye on your machine’s condensate trap and remove any water promptly, and always before you put it back into your bag. 
  • Make sure the flue probe is connected to the analyser before turning the analyser on (to purge the probe and instrument) and until the instrument has switched off (so that the probe is purged as the machine shuts down). 
  • When you take a sample from the flue, make sure the tip of the probe is in the centre of the flue. This puts the thermocouple in the hottest part, which provides the most accurate temperature reading and efficiency calculation. When you have taken your readings, put the flue inspection cap back on. 
  • Don’t put your probe in the flue and then switch the boiler on – this runs the risk of excess CO ruining reducing the lifespan of your sensor. 
  • When finishing a job, wait for the device to switch off, then remove the probe and then put the analyser in the bag. NEVER put the analyser in the bag whilst the instrument is shutting down or purging, because if you do, debris from the bag may be sucked into the instrument and cause damage. 
  • It’s dangerous to leave your analyser in a vehicle overnight. Not only could it be stolen, but overnight temperature fluctuations can lead to a build-up of condensation inside the device, which may cause it to malfunction. 
  • Only initiate start-up and purge in clean, fresh air (i.e., not in a room with the appliance already running).  
  • Take care of your flue probe; if it’s not completely air tight it may draw in ambient air and give inaccurate readings. Top tip: if you cover the end of the probe that usually attaches to the analyser and then blow through the other end, you should not be able to blow right through the probe. If you can, it’s leaking. 
  • When you have used the flue probe, let any condensate drain out.  
  • Check filters regularly and discard any that get dirty or damaged. Always carry spares.
  • Keep the display screen and buttons clean, for ease of visibility and use. 

Cared-for analysers live longer 

While there are quite a few rules for analyser care, most of them become second nature over time and are well worth sticking with. A decent flue gas analyser/combustion analyzer is an important investment, but with a little care and attention, that investment will last you for many years. 

To find out more information about flue gas analysers/combustion analyzers visit our solution page.

The importance of annual calibration for your flue gas analyser/combustion analyzer 

For many heating engineers, the flue gas analyser/combustion analyzer is vital kit; so much so, that most would have problems working without one. However, calibration and servicing generally require the engineer to send the analyser away for a while. That’s why, when the annual calibration date comes around again, some find themselves tempted to put it off, just for a while … 

Please ignore that temptation. It is absolutely vital to get your flue gas analyser calibrated every year, and failing to do so could cost you your job – or worse. Prompt annual calibration is simply not negotiable, and in this blog post we’ll explore the reasons why. 

Annual certification required 

A flue gas analyser is safety equipment and its accuracy may be – quite literally – a matter of life or death. The  sensors inside flue gas analysers react with the gasses they detect and degrade slightly over time. Compiled over the course of a years active use, the degradation can lead to inaccuracies in the readingsAdditionally, like any equipment, things can go wrong and parts can fail; that’s why all flue gas analyser manufacturers require an annual certificate of calibration, and the impact of not having one can be legally, financially and personally disastrous. 

Imagine, for example, that an accident has occurred and somebody or something has been harmed because your flue gas analyser failed to detect an issue. If that analyser was uncertified and had not been calibrated within the time period required (which would be easy to ascertain, since gas reports have the relevant times and dates printed on them), then you and/or your employer may be held criminally and civilly liable for this, having failed to exercise your duty of care to your client.  

That’s why, if your combustion analyzer is showing any signs of failure, or if your annual calibration is due, you need to book it in promptly. 

What about costs? 

Sometimes, engineers are tempted to put off calibration for fear of the costs. And yes, there may be charges involved due to damage or wear and tear: but what price do you put on safety (both the safety of the people you serve the security of your own job or business?) If cost is an issue, there may be ways to mitigate this. Manufacturers know that calibration is a recurring cost and some offer pre-pay options to make this easier to manage; some offer pre-pay options for parts as well. If you’re not sure whether this is the case for your device, it is worth talking to the manufacturer because the savings can be substantial. 

What happens during calibration? 

During its annual service and calibration, your flue gas analyser will be checked over and any components (for example, an oxygen sensor) will be replaced as required. A known concentration of certified test gas will be passed into the analyser and the instruments software will be adjusted to make sure it takes into account any drop off in sensor response and to ensure the analyser responds appropriately to all gases across the range of detection.  

Don’t wait – calibrate 

As you can see, calibration and any associated changes are vital to the functioning of your analyser, so you should never postpone or overlook your annual calibration: in fact, you must not use a flue gas analyser at all, once the previous calibration has expired. This applies however often (or not) you use it: the risks are the same.  

To find out more, visit our dedicated HVAC page.