- 26 Jun 2010
- Reaction score
As I stated in my thread starter.."all replies gratefully received."
The Vokera Vision Plus 20 S (Obviously you can substitute an alternative brand for comparison).
740 x 420 x 275 (the boiler connections are at the bottom so you’ll have to run them down the side if they’re from above as the spacer kit may bring it past 300mm).
Stainless heat exchanger serviced from front
19kW to 3.41kW
Personally I have that running with the EPH ember system, two heating zones and priority domestic hot water all on OpenTherm and controlled by app in a property I let. The thermostats are not the prettiest but they work. An external sensor can be fitted too if you wish to factor in weather conditions (I would).
If you run it with existing ON/OFF controls the efficiency % hit would be around 3-4%
Range rating is easy push button but better if the installer does it.
Hard to quantify ‘whisper quiet’ judgements but the sound power is 50db and obviously less if range rated. Your Baxi should have an energy label to show its sound power. All manufacturers should give you this on the energy label.
As an example to compare roughly to your daughters house a four bed 10 year old 1 bath, 1 en-suite I did a heat loss for came in at 9.4kW when -5 degrees and 5.05kW at +10 degrees. An 90 year old 4 bed detached 15.65kW at -5 degrees and 7.87kW at +10 degrees. These losses will be quite a bit lower when controlled with good controls as the house will be kept at a thermal equilibrium. I find it useful to mention losses in milder weather as that gives a reference to modulation rather than just quoting 1:5 or whatever.
18,000kWhrs/annum equates to roughly £810 @4p/kW NG so every % saved is £8.10p