Advice please for fixing a Heated towel Radiator

[rotadays]

I am looking for advice please for fitting a heated towel radiator to my newly fitted bathroom.
The rad will be fitted to 30x60 porcelain tiles fixed to plasterboard dot and dab on an external wall thermalite blocks. The radiator is large weighs 19.7kg so I am looking for suggestions for suitable fixings, the rad has come with rawplugs and screws but just wanted to make sure they will be sufficient.
Also if raw plugs are ok do you suggest tapping the raw plugs halfway into the tile to prevent possible cracking of the tiles.
Thanks in advance for any advice.

 

[muggles]

Drill through into the Thermalite, tap your plugs through into the Thermalite and use big screws

 

[rotadays]

Thanks for the advice, just a thought, has anyone ever drilled the hole through the tile and plasterboard and if there isn't any dot behind the plasterboard to inject some tile adhesive into the void? wouldn't this help?

 

[leakydave]

Use 4" screws with a rawlplug deep into the thermalite block.