Using Openreach ONT in a loft

Putting aside the practicalities of ending up in such a situation, but has anyone any real life experience of having an Openreach ONT in their loft, and lived through a spell of UK 40C weather with it ?

(I see the rated max operating temp is 45C)

Asking for a friend !

I have had broadband equipment in my attic for the past 8 years without problems. The euipment is powered up so keeps itself warm enough to work in the winter and still worked in the hot summer. Inland Kent.

No way, the loft will get 50C in hot summer . ONT will be burn out!

The forum member MHC has his ONT in his loft.

The issue you face is whether the installer will provide it where you wish.
For starters the loft needs to be properly boarded out, adequately lit, have a proper power supply, a properly installed loft ladder for access.

I believe MHC provided tubing and draw cord from the eaves to where required.

Solid state electronics can generally get hotter than 50C without issue. The mechanical hard disks and fans in servers are often the parts that fail first. I saw this in a server room where the AC failed and it got to 68degC. Not pretty 😂

I've had ONT, router, NAS and PoE switch in the loft for years.
It's the PoE switch that was perhaps not the wisest move - that gets hot... but hasn't malfunctioned... so far.

Correct and been there for three years at least, including the 40c days in 2022.

WRONG.

I have all my kit in the loft - ONT, router, 24-port switch, DECT/IP base, file servers, etc., with no issues over the last few years.
The loft 'floor' has the usual glass fibre mat and to make the space usable I added insulation - basically an aluminium/bubble wrap sandwich - stapled to the rafters. This has 3 big advantages: it isolates all the dust from the 50-year old roof, it keeps some heat in during the winter, and it reflects the worst of the summer heat. With partial boarding and a permanent folding access ladder it's a very useful area.

Thanks for all the responses, 50:50 sort off. I'll forward on all the thoughts and observations.

I've also thought about having the ONT in my loft when the time comes (when ever that might actually be) I've got a 80% boarded loft, loads of permanent lighting, loads of power available, and a permanently installed loft ladder. In fact my wife often invites me to spend as much time as I like up there . I have my overengineered RF distribution system there, using semi industrial grade active kit, never had a problem, but that equipment is designed for harsh environments.

When the time comes, I'll run some 20mm flex-plastic conduit from the gable end, to the floor 'trap' that leads down into my technology cupboard below, but that would be contingent on the Openreach (or whoever) engineer agreeing to that scheme. It's a shame there isn't an advance visit to discuss options, all I can do is prepare provisions in case my ideal routing is accepted. (It would also require the CSP to be inside, on the gable end wall, so ever slimmer chances....

I suspect I'll end up with an external run from gable end, down to ground level, and a CSP on the wall below my study window. Having the ONT in the study below the window would work fine for me too.....