As far as I can tell the temperature is stable. This heater has the most reliable glass tube heater cover. That was the reason for my purchase decision. I will not recommend these heaters to anyone. They look great, the mount is the best on the market, the problem is they have temperature drops which makes them unreliable. I have 4 pieces of them and initially they worked ok From 3/4/2021 I would advise you to save money and buy another brand.
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