hopTop Transformer Operating Temperature

Sorry this is a bit off topic but I haven’t been able to find the answer to this from Reddit, manufacturer website, Amazon, or general googling. Thought folks here may know.

I’m trying to figure out what the operating temperature range of the below linked device which I was hoping to power a smart thermostat. I was considering putting this in my attic where the temps get pretty extreme (125 fahrenheit, maybe a little more in summer, below freezing in winter).

Any ideas?

24VAC, 40 VA AC Transformer Plug in with PTC Fuse Compatible with Ring Nest Doorbell UL Listed https://www.amazon.com/dp/B083R621RV/ref=cm_sw_r_awdo_5FN018J4TT9VRS2BFQ4E?psc=1

The manufacturer answers questions posted at Amazon, I would ask there.

It’s UL listed, but not rated for outdoor use. The manufacturer’s answer to a previous question said that the top temperature range was 140°F. They didn’t give a low range.

Since it’s mains powered and UL listed, I would expect it to go down to at least 30°F, but it might be lower, again, you should ask the manufacturer.


I don’t see the usual place to ask questions on Amazon, which is strange and why I posted here after also searching various other forums.

Where are you seeing 140F for example?

sounds like some type of blocker installed … most likely on your browser

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It appears for me in the usual place, right above the reviews. @jkp noted, A pop-up blocker might prevent it from appearing.

Bizarre, when I use a different device I see it. Thanks!


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