It would eventually shut off if temp got high enough. I think for a Drayton trv4 this is about 30 degrees. In practice, however, it would be difficult to get a room up to that temperature and, really, why would you want to. So in the real world, putting the trv to max will keep the rad on until other controls turn it off.So would just stay on till run stat turns it off?
Plus you don't notice they are rusting until they burst.Openings on the top will help but panel radiators have been designed to maximise heat output into the room. Putting a cover over it will slow down that heat transfer. I've never really understood why people seem to have a problem with the look of panel radiators and I can't see that they are improved by the addition of a MDF box.

it had a fan in the bottom, with speed control, and two thermostats, one on the water pipe, and one measuring air temperature so the fan would only run when the radiator was hot, and also only when the room needed heating.
to try and turn a standard radiator into a fan assisted radiator, the output of the first on is adjustable 2 watt the power supply has a range of voltages
so you can reduce the speed, and with a fan you could box in and the radiator and TRV will likely still work, it seems they use cooling fans normally used to cool computers, so suppose you could make your own.
is needed to turn fan on only when radiator is hot. I would also paint radiator mat black before boxing it in, as that colour radiators heat better. As to room temperature control you can get TRV's with a remote sensor
so there is no real need to set it to max setting. Think I would put the TRV outside the enclosure so can still use a smart TRV head.If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
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