Cannot shift CH airlock

[MikeAustin]

Well, the system has gradually been getting worse so I called the company that installed the boiler (Viessmann Vitodens 100C) to do a service and check on the boiler. The temperature does not go above 60C, dropping back to 41C and then heating again on only 2/5 bars.
When the guy arrived, I switched off the CH and HW and, as he opened the front panel, the boiler fired up - and rose to 90C! That is without any external demand. Clearly, something is seriously wrong with the control board!
I had this boiler installed in 2005 and had the board and a couple of sensors replaced in 2009. They cost £193. Now they cost £380! So I have had it with Viessmann and will probably go for a Worcester 15RI. He quoted a total cost for supply and fitting of £1,891, but I am sure I can do better than that.

 

[TCCHeating]

So I have had it with Viessmann and will probably go for a Worcester 15RI. He quoted a total cost for supply and fitting of £1,891, but I am sure I can do better than that.

Well Worcester have won the which best buy award for the last 7 years so I commend your choice of replacement boiler sir.............

Right.... Now where has my damn unicorn gone. Bugger keeps running off with my crack pipe... Must dash. Bye.

 

[45yearsagasman]

There's absolutely nothing wrong with WB Ri boilers. Its the poor installation on dirty systems that causes problems with the best of boilers. That is the fault of shoddy installers. Before I retired I attended many Ri installs and rarely found a problem that was entirely down to the boiler. My own 18RI is quiet, reliable and as efficient as any boiler. It replaced an old wall mounted Potterton.