Learning how the air conditioner at school works

I learned a bit about air conditioning maintenance from the a/c representative

It had been a rough week at school. My sinuses had started acting up, and the constant sneezing from the allergies was not helping. The students and staff alike had noticed that the air quality had decreased significantly. The high temperatures of spring during the day were causing our comfort. The headteacher gave us a free class after receiving confirmation from the air conditioning supplier that the a/c representative was coming. The school maintenance department contacted the air conditioning company early the previous day. The air conditioning business had an influx of calls. It was a/c repair season, and finding an available a/c worker was nearly impossible. We finally had booked an a/c care plan, and now the servicemen would visit the school to check the air conditioner. Though other students left, I chose to stay as I was finishing some homework and my parents would not be home till late, so I opted to stay in school. It was much better than going home and waiting for my parents to get home. They asked about the air conditioner installation and the observations that we had made. After collecting this information, they proceeded with the a/c care. Part of the a/c service was replacing the old with a new air conditioning filter to ensure the system was functioning optimally. I stood close to the technicians for nearly three hours, observing them working. I learned a bit about air conditioning maintenance from the a/c representative. I also learned about these HVAC units and how they work.
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