Heating engineers are competant at HEATING, ie water, pipes, boilers.
Electricians are competant at ELECTRICITY, ie wiring, controls, sockets, switches.
Have yet had a need to call an electrician to do controls for me. No doubt there are sparks out there that can wire control systems on boilers but they must be very thin on the ground.
A S plan I installed when I fitted a boiler was totally screwed after the client got an extention built with underfloor heating coupled to my S plan.
Also, why is it that folks cannot follow the standard strip connections Honeywell and other control makers show in their wiring plans. Majority of the wiring I see is single connectors on wires making faulting a major PITA
Now I am going to retire to my bunker and watch the tirade unleash.