Weather Compensation

[DursleyDonkey]

I don’t want to discuss the arguments for and against Weather Compensation – it’s been done on other threads. So for this thread, can I ask you to make the assumption that WC is a given – I’m planning to buy a gas boiler that includes it.

Could I ask those of you with experience of installing, servicing and using domestic central heating with weather comp, which systems you would recommend and why? I’m looking at replacing an existing boiler with a heat-only system of around 25 kW (existing boiler is 23.7).

I’m aware that Viessman do WC and seem to sell it as their thing. I’m also aware that it’s an option on the Vaillants, though they look a tad more pricey. I’ve also heard that some systems can use internet data to avoid the need for an outdoor sensor – but don’t know which systems. Which other brands offering this, and what experience do people have with these? What are the most reliable, best value and what issues do I need to be aware of?

Many thanks.

 

[Agile]

Some boilers like Vaillant need a separate and expensive controller.

Others like Viessmann, Intergas and Biasi have it built in so that all you need is nthe cheap sensor.

I don't like the area data used by the Nest etc. but would always recommend your own sensor as that's spot on for your area and takes account of showers and clouds etc.

Tony

 

[vulcancontinental]

Most other brands will offer some sort of compensation and I am also unsure of internet based data, two or three degrees out will result in a quite inaccurate flow temperature. I work for Vokera and all ours bar one can have the sensor wired to it or internet derived. Whatever you choose try and find one that will give you internal temperature control as well, a modulating thermostat as then the internal demand can be referenced along with the external temperature. The construction and exposure of the property is also important although people seem to place less emphasis on this. Try to find one that can be tuned to act in line with speed of loss through structure and frequency of sampling.

 

[mrshr]

Whatever you choose try and find one that will give you internal temperature control as well, a modulating thermostat as then the internal demand can be referenced along with the external temperature. The construction and exposure of the property is also important although people seem to place less emphasis on this. Try to find one that can be tuned to act in line with speed of loss through structure and frequency of sampling.

That's a good point.
I have a vaillant eco tec boiler and would like to go down this route.
Can you recommend something that would be suitable please?

 

[vulcancontinental]

I'm afraid I don't know about Vaillant, they use their own protocol, ebus. Tado can work with .this protocol but how well and comprehensive I know not.

 

[Phill Peck]

That's a good point.
I have a vaillant eco tec boiler and would like to go down this route.
Can you recommend something that would be suitable please?

Combi or system

 

[Doggit]

I think the Vailant system is about £140, and the controller is the indoor sensor with an outdoor sensor positioned on a north wall. But it's not an easy system to understand, as you have a lot of heating curves to choose from, and no real instructions in the manual to actually explain what they do.

 

[vulcancontinental]

They are not alone in that.

 

[muggles]

Intergas do good weather comp, packaged in an extremely reliable boiler with a 10 year warranty

 

[Razor900]

A modulating thermostat will give far better returns than simple WC. Make sure that whatever boiler you chose can differentiate between the hot water and heating functions as you will need a separate flow temp when reheating the cylinder

 

[vulcancontinental]

I forgot you were looking for a new boiler and thought you were adding to the Vaillant.

The Vokera evolve boiler will do what you want with either internet weather, wired or RF external sensor.

Fitted with BeSMART there's a 10 years warranty and an A+ ErP package rating for heating. Full remote control and boiler reporting and reset plus zoning if you require.

The WC setup you see explained below is embedded onboard with the REC 10 boiler interface however it is overriden by the BeSMART which has it's own settings that are not as flexible as those below unless you use it as a simple timed room thermostat without the full remote control option.

You get 7 years warranty on the boiler without the BeSMART as it's part of an incentive offer which ends at the end of December




I think Razor is correct in that the internal reference is a preference but ErP reckons 1% improvement and that will depend on the structure of your house. The parallel time reduction on a timer will handle that fine.

 

[mrshr]

Combi or system

System

 

[Phill Peck]

System

You’ll need to use Vaillants own control system.
So that the boiler knows wether it is doing heating or hot water.

 

[Phill Peck]

System

What area of the country are you in?

 

[Wally©]

I had a Viessmann 26kW Vitodens 222-F B2SB 130 liter combi boiler installed last March...
Though the WC is something you have to adjust to it hasn't given any problems so far...
But you need to learn about the heating curve/inclination...
DHW production is truly great...
Right now...with an outside t° of 8 degrees and room temp set at 21° it's condensing
at a t° of 43 degrees...