My normal job is as an electrical engineer for a company that manufacture automated production processes. However, over the years I have had several friends that are either RGI's, or employ RGI's to work for them that I help out electrically when they, or their usual sparkies get stuck. Normally this would be with modifications to an existing installation, or with faultfinding. The vast majority of the time I help them over the phone or email them a CAD wiring diagram, but occasionally, I attend site to assist them. With any new system, they will always complete the final installation and then commission it.
Most combi's are quite straightforward to wire, so they can do that on their own. It's usually S-Plan & Y-Plan conversions that I get to see, so there's usually no need to open up the boiler to access their wiring terminals then anyway.
Interestingly, a colleague recently had a new combi boiler (Ideal Vogue Gen 2) fitted along with a Nest Thermostat that he specifically requested, specifying that he wanted to used Open Therm. The Gas Safe installer didn't understand OT, so wired it up to the normal way with the dry contacts. My colleague who works in software (Brilliant guy, but not good with wires) asked me if I could change it over to OT, so I arranged to meet the RGI there who removed the boiler cover, watched me change the wiring over, replaced the cover and left, and that's it. Not a single check made! and to coin a phrase "Not the first time I've seen that either"
Also, when I said:
Not the first time I've seen it either.
I don't recall mentioning seeing it "on-site" It could well have been in another thread on here.
I trust that clarifies your enquiry.
