training courses

Good Morning all,
wanting to know if anyone can point me in the direction of a training course / school / manufacturer lead training program?
I want to improve my diagnostic skills on modern chiller / freezer van systems ie hubbard / GAH for example, i dont do many to be fair, mainly pipe repairs, probe replacment, leak repairs, but feel i am very much on the back foot where, the above mentioned is not the fault for lack of operational performance, ie electric issues / correct test proceedures for stand by operation etc..
Do such courses exist for indipendants? or is it a closed shop and those independants are ex-tec's from manufactures or self taught?
I should point out i am refreriing to the UK market here.

Any advice will be accepted gratefully
Thanks
Pat

3T services in Runcorn might be one to have a look at, David Luckett seems to be know a think or two, I think his background was in R&D/design for Carrier. Last time I spoke to him he said he would do a course to meet individuals requirements.