Base for External oil boiler

[Pippy102]

Hi I’ve just had an external oil boiler fitted - it has been sited on some patio slabs I had - my concern is that two of the slabs have not been put on a proper base and are just on clay soil - the other two on the path appear to have been “levelled” with clay soil. The plumber has told me a wet & dry mix has been used - but one of the slabs definitely moves if I stand on the corner - the weather was extremely heavy rain when this was being done

Also I am not sure if the patio slabs can endure the heat of the boiler when maybe combined with cold air and if this could cause them to crack. They were old slabs that just happened to be where I wanted the boiler put. I replaced an old internal boiler.

Appreciate any advice

 

[Exedon]

No heat involved at base of a external boiler they are insulated
Having said that a bit of digging out and some consolidated hard-core before the slabs would not have gone amiss.