Calling my landlord for an HVAC issue

I rent a very nice house in a great neighborhood. I certainly hope to own a home one day, but I am still glad that for now, the landlord is the one that deals with the vast majority of issues that I face with the home. I do basic things like refill the water softener with salt and change the air filter for the HVAC system. I never really had a problem with the HVAC system until recently. I woke up one morning to discover that it was very warm in the house. I figured that my roommate had merely changed the temperature on the thermostat on me, but then I went to check it and I found that the cooling function was simply not working. At that point, I wasn’t entirely sure whether I should be the one to call out an HVAC technician or if I should have the landlord do it for me. I figured that if I called out the HVAC technician, then the bill might be on me, so I called the landlord first. He ended up being the one to call out for an HVAC technician. He explained that I had done the right thing by calling him first, because it was his responsibility to take care of any major HVAC issues. He did ask me if I had been changing out the air filters for the HVAC system regularly. I responded that I had been faithful to change the filters and I wasn’t sure what the problem was. The landlord reassured me that the HVAC technician would take care of the problem.
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