It is always poor when you have high hopes for a product, & they just completely fail your expectations. I had that recently with a portable Heating and A/C unit. Periodically in the summertime our living room can become legitimately hot. I don’t guess why it is, however our living room is always the warmest in the entire house. Naturally, this can make it strenuous to sleep periodically. Even though our central Heating and A/C runs perfectly fine, it never seems like our room is cool enough. So, I decided the best solution would be to get a portable Heating and A/C system to support the main central cooling system. This way I can get regular sleep. I went & bought the portable cooling system from a local Heating and A/C store, & for the first week, it worked beautifully. Every single night that I had that portable cooling system running, I slept for seconds. I never realized how much sleep I was losing thanks to temperature. Everything was going well, until it suddenly wasn’t. A little over a month later, I wake up in the middle of the night & our room is back to feeling boiling. I was confused, did I forget to turn the portable cooling component on? I had a clear memory of turning it on. I went & checked on it, & it was off, however I couldn’t get it to turn on again. I ended up returning the portable Heating and A/C because of this, & then bought another a single. Thankfully I didn’t have any additional concerns.