Replace timer for 400w immersion with Sonoff T1?

[abroad]

Hi all,
I've got a tiny 400w heater in my bathroom towel radiator. It's controlled (as a fused spur) by a dumb timer switch, which is at the back of a built-in wardrobe in the bedroom.
I've got the twin&earth coming into the metal back-box, and another twin&earth heading out to the heater.

I want to be a bit smarter, only running this if the heating hasn't been on (which I monitor from my Nest via node-red), at different times on different days, and not if I'm away.
The Sonoff T1 'touch' light switch seems cheap at a tenner and flashable.

My questions:
Is it electrically safe to use this device (or any light switch) to switch a 400w heater? (Spec says Max. Power: 600W/gang.)
Will the 'touch' light switch be activated by clothes brushing against it (remember it's a the back of a wardrobe!).
Are wifi switches OK with a metal backbox?

Any alternative devices or approaches, or other advice much appreciated.
Cheers,
Tony

[toscal]

Just to clarify is it an immersion heater (hot water) or a towel rail.
I think most immersion heaters are resistive in load and so are towel rails. You need to see what its load rating is. Personally I would use something like this or this one.
It could work after all the load of the towel rail is just under 2 amps, and the rating of the switch is about 2.7 amps. Most light switches will say if it can be only used with normal lighting, Flourescent etc. Most normal lights (halogen bulbs) are resitive while LED and CFL are inductive (or capacitive)

[abroad]

Hi Toscal, Thanks for your response.
It's a towel radiator like this (if my link works), so in the winter when the central heating is on it heats up like a radiator, in the summer I use an electric element to heat it like this.

I will research resistive vs. capacitive; I would expect it to be resistive.
I have something like the products you show, but for fun I want something wifi, so, for example, when my solar panels are exporting to the grid I can turn it on for a few minutes to dry the towels; if my phone is out of the house overnight it doesn't bother using electric; etc. etc.

Thanks again,
Tony