You have a misguided idea of manufacturer's training courses. They only last a short day and are mostly about sales promotion and a little information which is delivered but is in the book anyway.
Very unfortunately, they are primarily a SALES opportunity to promote their boilers. There is never any assessment so anyone attending could sleep through the whole day and still be added to their list of approved installers!!!
Tony
Very true Tony.
The manu's know the installers are mainly the ones with the choice of which boiler gets fitted and the training courses and installer approval along with freebies, is just a way of "hopefully" getting them on board to sell their stuff.
In the morning they show you the product(s), explain the sequence of operation and tell you how great they are and how little they break down and if they do break down what excellent level of service you will get.
Break for lunch then show you some little tricks to save time when servicing or fault finding (which can be interesting).
Repeat how great they are and how little they break down and if they do break down what excellent level of service you will get and give you a goody bag with some brochures, pens mugs and stickers etc. And a couple of contact numbers. All highly technical stuff
Any decent installer could flick through the book while having a cup of tea and fit the boiler no problem.
There is a bit of difference between fitting a boiler and fitting an engine.
A boiler just bolts to the wall in a particular way. A flue attaches in a general industry std way and the pipework attaches in a std way too. Upon commissioning again std practices are followed but with small differences between the manu's.
The installer will not be doing any work to the boiler other than fitting and commissioning so does not need to know the intricacies of each particular boiler.
I fit mainly Vaillants or WB and rarely have to look at the book as i have fitted hundreds so know the procedure off by heart.
If i am servicing/repairing them i may need to check the service book more often. Only because i mainly install.