Here’s why we stopped installing Viessmann Boilers many Moons ago……
2002 – 2008
We only installed Vaillant Boilers, we had been installing the Vaillant Turbomax Combination Boiler and the Vaillant Thermocompact Boiler for many years, these boilers are some of the best boiler ever made, they are super super reliable. They were then replaced with Vaillant Ecotec Range of Boilers.
We learnt there was a manufacturer design defect on the Ecotec boilers which lead to the heat exchangers catching fire, we stopped fitting them immediately as we are the experts to many TV and Radio programmes and didn’t want our reputation damaged by fitting a defective boiler and then having to have a conversation with a customer that goes something like this…….
Hello Mr Smith ……sorry your boiler caught fire.
We had to select a new Boiler Manufacturer.
Potterton, Baxi and Main Boilers (all the same boilers with different brand names) couldn’t be bothered to send an a sales representative to meet and discuss us selling and installing there boilers – Bye Bye.
We decided to try Worcester Bosch and Viessmann Boilers both German Boilers.
Viessmann Trial
A German Customer in Tottenham insisted that we quote and install a Viessmann Boiler.
We installed a Viessmann 100 kw 30kw combination boiler in an ex local authority house (8 radiators,1x bathroom) with Viessmann plug in boiler timer and wireless room thermostat.
The boiler heating had a mind of its own and could not be timed.
Viessmann sent 3 different engineers out over 1 month, each engineer said something different…but all blamed us. One engineer who had come from Watford told the customer that we had failed to install a Low Loss Header and that was essential ….he couldn’t have been more wrong if he tried, the other 2x Viessmann Engineers inc the commercial engineer told the customer this was wrong. I contacted the MD about this low loss header nonsense and he said …we stand by the engineer.
Now we had unhappy customer who blamed us (understandably the customer believed whatever the Viessmann staff had said).
Solution
I gave the customer £120 cash and told them to call (& pay) any independent expert and get them to look at the boiler – customers expert said it was definitely the boiler and found NO fault with our work.
I called and wrote to the Viessman MD….in the end Viessmann reluctantly sent out and engineer from their Commercial Boiler division (who had worked in the domestic boiler division)
He discovered that our supplier had given us European type plug in programmer which is not compatible with UK boiler – Viessmann sent us the correct UK plug in timer £foc
4 days later we installed/plugged in the timer into the boiler…….however ….this did not solve the issue.
Viessmann sent back one of the original engineers and he again blamed us, this time the customer called the Managing Diretctor of Viessmann who agreed to send back the Commercial Viessmann Engineer …..he returned days and spent an hour on the phone to Viessmann Germany.
The issue (if this helps other installers) – the boiler PCB (printed circuit board) did not recognise the new UK timer as it been ‘sync’d’ with the previous European PCB, solution – order new UK PCB and UK timer
The commercial engineer returned a week later and installed the UK PCB and timer – problem solved
But was it solved ? The customer had spent a large chunk of £money with us £2300 + vat and had no real heating for 7 weeks, it took 7 weeks for Viessmann to solve this and this was a freezing January winter.
Viessmann MD emailed me and asked me NOT install any of their Boilers – this was the only sensible thing he had said to me.
We then trialled installing Bosch Boilers and have never looked back.
‘London Boiler Company are an important Customer’
– Carl Arnzen CEO
January 2024
A new Customer contacted us and asked us to look at his Viessman 100 System Boiler which was not heating up the radiators very well.
Our engineer called Viessmann technical who confirmed the boiler pump was faulty and suggested there could also be an electrical issue. We advised the customer to call Viessman directly and get a fixed price repair which includes new parts and labour.
The Viessmann engineer changed the pump head section (not full pump) only and left the leaking pump automatic air vent in place? The boiler worked for a few hours and went back to not heating the house properly.
The customer called us back, the system was very clean, but we did keep finding large black lumps inside the boiler.
Viessmann Design Fault
The rubber hoses inside the boiler are not robust enough to cope with the heat and they deteriorate and black debris from them blocks up the boiler heat exchanger which causes poor heat output to the radiator system.
Video displayed with kind permission of Allen Hart (Engineer) Leeds
Our advice, just install a Worcester Bosch Boiler with 12 or 14 Year Warranty
