Advice on Upgraded Heating Installation

Thermostat and overheat thermostat on the boiler could fail. Highly unlikely series of events but it could happen.

I can see your point, but;

It's an oil boiler so is more likely to be able to get hotter than 80C in a fault situation.
In the scenario of the pressure valve sticking, the cylinder could rupture. Something will give, that is for certain, flooding the house with (initially) very hot water.



The whole point of the G3 regs is to have two lines of defence if there is a problem. G3 was meant to ensure a potentially dangerous but useful domestic appliance can be safely and confidently installed by semi skilled people in a consistent manner.

Here we have an installer who, even though the manufacturer and the law have provided abundantly clear instructions, has, through their own negligence and lazyiness, chosen to ignore them. Sadly, I and many others in this industry see this type of install all to frequently.

And usually the customers tell us what a nice chap installed it.

Yes there are some basic mistakes on the installation and it needs sorting but posting videos of cylinders exploding is a bit over the top, if the stat and o/heat stat failed on the boiler and the tprv stuck and the cylinder stat failed and nobody noticed the terrible racket the boiler was making it might explode, thats a lots of ifs.

More likely to overheat if the immersion stat failed and kept the immersion heating the water...having said that the immersion doesn't appear to have been connected!