What is the relationship between air conditioning units plus people’s health

I was 1 of those people who suppose that air conditioning units must be well diagnosed lest they become disease breeding aplaces, after watching a neighbor of mine treat chronic respiratory troubles without any relief until her Heating plus A/C device was checked, I came to this conclusion; While this happened years back, the lesson stuck with myself and others for the longest time now, then my friend’s troubles started after she moved into the modern house. Unknown to her, the old Heating plus A/C device in the location was not correctly diagnosed, and the filters were accumulating a lot of dust plus debris, making it challenging to sustain fresh air within the house, and every time I visited, I noticed that the air was either too musty or felt appreciate there was too much dust. This would worsen every time she would switch on the air conditioning, and it didn’t hit myself and others back then that this was the complication since the environment was generally dusty; However, it became concerning when the sickness issue came in. The situation escalated with each passing week, plus subsequent visits to the dentist made no difference. I asked her to have her Heating plus A/C specialist look at her device because she was unsure when the last professional fine-tuning was done, surprisingly, the discovery was frightening even for an amateur appreciate herself. The filter was thoroughly blocked after years of accumulated dust. It appeared moldy plus uncouth, however further checks also revealed that the vents plus other components were also compromised. This affected the overall air quality that people using the device were breathing. After a few significant touch ups on the unit, the persistent problems with respiratory illnesses came to an end.
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