I recently cleaned my home's air filters and discovered a significant increase in well-being. Previously, staying at home during the weekend for more than 1-2 hours resulted in fatigue and dizziness, whereas being outside or at work during the weekdays (indoor environment with commercial/industrial-grade HVAC) did not.

My carbon monoxide detector couldn't find anything so CO was not likely the cause of the problem. Conditions also improved when the heating was turned off.

After the cleaning of air filters (edit: there was a lot of unknown black material stuck in the filters during the clean), no such fatigue nor dizziness occurred, even with heating turned on.

So based on this experience, I suspect the difference has something to do with the concentration of leaked natural gas compared to air flowing through the filters into the house.

Is there a recommended method and tool to detect natural gas, or any more accurate cause of the problem, so that I can better detect and prove such a phenomenom (something causing unusual fatigue and dizziness over time) in any given location, especially when changing air filters myself is not an option?

  • 3
    Natural gas stinks, so you know there is a leak. Clean filters would probably let more gas type though. Thinking maybe more of a mould type problem, but your symptoms can be cause by many things. Location and type of house might help.
    – crip659
    Apr 12 at 23:48
  • There was never any noticeable smell, even beside the furnace itself. I'd like to hold off on the location if possible, but the type of house is a fully-detached / independent type. // If it helps, there was also some black material stuck onto the filters (which caused the water container it was in to turn dark gray) during the clean.
    – plu
    Apr 12 at 23:58
  • 1
    Location does not mean your address, but country/state might help. Thinking you might have a super-duper air tight house. Did not say what air filters were for, maybe air exchanger and might have a carbon dioxide build up. Opening some window and letting fresh air in might solve problem. Black material might also be bad mould and should have it tested now.
    – crip659
    Apr 13 at 0:14
  • 1
    significant increase in well-being there may be other factors ... did you open windows during the day more often? ... is there more daylight in your house?
    – jsotola
    Apr 13 at 0:21
  • Think getting brand new air filters might be good idea, especially if mould is causing problem. Cleaning filters again with bleach is next good idea.
    – crip659
    Apr 13 at 0:41

Natural gas has a chemical called Mercaptan the human nose can detect this at ~1 part per billion so probably not that.

Excess carbon dioxide the stuff you exhale can cause your symptoms and newer tightly sealed homes can allow the carbon dioxide to build up.

You may have make up air on your furnace a small amount drawn in from outside.

Because of dirty air filters your make up air was not being drawn in, or not in sufficient quantities to purge the excess carbon dioxide.

Clean filters equals more air exchanges in the furnace and if there is a make up air line drawing in some fresh air more air reducing the excess carbon dioxide. If no make up air the higher air flow mixing the air in the room.

It could just be cabin fever as one comment suggests but I would also look to air quality.

  • Given CO detectors cannot detect CO2 (gaslab.com/blogs/articles/…) and other gases, I'll give some of the other detectors a shot. // I could monitor things and record differences over the next couple months as the filter gets dirtier.
    – plu
    Apr 14 at 4:10
  • 1
    i don't know if you're a maker, but there's many cheap (~$5) sensors that (relatively) simply plug into the arduino platform; dust, CO/CO2, NG, O2, etc.
    – dandavis
    Apr 14 at 22:07
  • Yes, can do that, probably the cheapest way to do it.
    – plu
    Apr 15 at 2:00
  • From the use of sensors over the last couple of months, it turned out the problem was CO2; there was a certain spot where the air just didn't flow well and putting a potted plant nearby helped, both with the CO2 and the elimination of those fatigue and dizziness symptoms. Thanks!
    – plu
    Oct 15 at 3:17

There are combined CO/NG detectors, very cheap. The best NG detector is your nose. Your air filter will not filter either of these gases, they will pass through. If you have an electrostatic air filter it might set NG aflame .... that would certainly alert you to it.

The stuff in your air filter could be grey, black, brown, white ... it really depends what particles are floating in your air. If you use your fireplaces a lot, or live in a city, or near a highway, or any place there is a lot of smoke you'll see black crud in your filters.

How long ago was the previous time you cleaned the filters? If they were neglected for a long time perhaps there was something in them, like mold, that would explain the health effects.

See here: headaches caused by CO, Formaldehyde, Pesticides. And here: CO2, VOCs (solvents), asbestos, lead, radon. Could any of these things have been long-lodged in your filters before cleaning?

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.