Can I use a Large propane tank with a BBQ with an appropriate regulator

witnessmenow

I picked up one of the Weber Q2000 that are currently on offer from Woodies. It comes with a clip on 37mbar regulator that fits a "patio gas" tank.

But we have two basically full 47KG propane tanks from a Gas fire we removed a few years ago. I was thinking with the
right regulator I would be able to use the weber with these. as it would be nice to get some use out of these tanks! This looks like the right regulator to me

But I was reading the weber manually and it specifically says: "Only use cylinders with a minimum capacity of 2,5 kg and a maximum capacity of 13 kg." Is there any reason why this would be like this? I would have thought once the pressure is right, the capacity of the tank wouldn't matter?

Sorry if this is a dumb question but I'm fairly new to gas and I would prefer to be better safe than sorry!

Also, I was thinking of adding quick release valves at some point, 1 to make it easier to disconnect the weber from the tank when putting it away and 2 to also have the option of connecting a pizza oven to it (same 37mBar needed). Was thinking of something like these, any reason why this would be a bad idea?

Thanks

Lumen

It's probably something practical like the hose not being long enough.

I have left the BBQ on a couple of times "sure I'll just burn off that mess" with a full tank and then forgotten about it, which is expensively annoying.

The Continental Op

https://www.boards.ie/discussion/comment/122345911#Comment_122345911

I seem to remember there is some regulation as to the max length of hose. Thats a safety thing which I can't remember the reason for. Still alive after using much longer hose.

Just wondered if the recommendation for the size of gas bottle was for one that would fit in under the BBQ anything bigger obviously wouldn't.