Originally posted by: green_star
I have only just seen this so it might be a bit late to be helpful. After 35 years of putting up with an electric warm air system I took the plunge of installing a gas-fired wet system last year. I got quotes from three installers from those on Which? Local in April last year and went ahead with one of these in October. In the meantime I had spent a considerable amount of time (much too much time)researching alternative systems. In the end, and with several misgivings, I chose a Viessmann 200-W boiler with a Vitotronic 200-HO1B weather compensated controller. This was the first such system that the installer had dealt with (one of my misgivings) but he found it straightforward. He was particularly impressed by the performance in terms of the (relatively) low water temperature from the boiler (i.e. not very hot radiators) to achieve the desired temperature in the rooms. This has been my experience over the 13 months or so since the system was commissioned. As I write, the outside temperature is 6 degrees with a cold wind and the boiler is running in the low 40's. I turned the heating on about two hours ago when the thermometer in my room showed about 16.5 degrees; it now shows 20.7 degrees and with the current settings this will stabilise at about 21.3 with the rest of the house (a 4 bedroom, 3 storey terrace) being suitably warm.
At first I couldn't really believe that satisfactory performance could be achieved without the assistance of an internal temperature sensor as a supplement to the external temperature sensor. Although Viessmann had a suitable device available this would need to have been wired in and they assured me that this would be an unnecessary expense. I'm glad to say that they were correct and that the Vitotronic controller has been very easy to use.
As regards costs it is difficult for me to comment. However my combined gas and electricity usage over the past year was about 18000 Kwh (3500 electricity, 14500 gas) which I realise is about the same as my electricity usage with the old system. However, the house is very much more comfortable in terms of the availability and distribution of heat. One last, and more relevant, comment: when my neighbours' flues are billowing clouds of steam mine rarely is, thus substantiating the claims of enhanced condensing performance.
I should note that I have no connection with Viessmann. In fact one of the reasons for my delay of 6 months was the volume of adverse comment about Viessmann boilers on various web forums and Which? itself 'advocating' Vaillant and Worcester-Bosch.
Hi green star,
Thanks indeed for sharing your experience – sounds like another endorsement for weather compensation.