Vaillant Boiler Choice

[diy_darren]

I've decided I'd like a vaillant boiler and narrowed the choice down to ecotec plus 837 or ecotec exclusive 838. Seems like there is only £60 between the two, is it worth getting the exclusive? Do the extra bits actually mean much?

I started looking at the control options and liked the look of the VRC 430. It looks like it's all the controls in one box, so I'd mount it where I'd normally mount a thermostat, is that right? That is bang in the middle of the house. There must be an external thermometer wire, is there any particular place that should be located? Any idea what length of cables come in the box for thermometer and connection to boiler?

 

[Agile]

Dont you plan to use external weather compensation?

Whats your CORGI installer advising you?

Tony

 

[simond]

VRC430 is weather compensation.

ecoTEC exclusive is an old ecoMAX dressed up ready to go out with some extra lights, thus the larger casing size.

If you want to know how to fit these bits - and isn't it time you got on with this task, Darren - just download the installation manual from www.vaillant.co.uk

 

[diy_darren]

Dont you plan to use external weather compensation?
Whats your CORGI installer advising you?

Yes, and he's not advised as I've not asked him yet. I'm paying him to pressure test my work, route the flue, hang the boiler, connect the gas, connect the controls and commission the system. Anything I can do safely in advance I will, which includes deciding positions for controls and routing any cabling.

I could ask him to come around and ask him all these questions, but some of them (and yes there's probably more!) are vaillant specific. That means he'd either have to read the manual, which I can do, or rely on information from installers who deal with vaillants on a regular basis.

just download the installation manual from www.vaillant.co.uk

Thanks for the kick in the right direction! I'd seen the manual titled vrc_430_operating_instructions.pdf but didn't realise it also contained installer instructions

 

[Agile]

VRC430 is weather compensation.

Does it also measure the internal temperature in the building and use that in relation to controling the boiler as well as the external sensor?

Tony

 

[diy_darren]

Yes, it measures inside and out.

http://www.vaillant.co.uk/stepone2/data/downloads/1e/43/00/vrc_430_operating_instructions.pdf - page 17

You pick a heat curve and using the outside temperature it calculates the most efficient water temperature to heat the house to the desired internal temperature.

I have no idea how you pick the right heat curve, but I'm sure a heating engineer will.

 

[Agile]

Actually its mostly a matter of trial and error although a data logger helps.

Its a function of the heat needed to raise the temperature inside to the target which is mostly related to the radiator sizes.

However, when it takes into account the internal temperature as well, then there is another factor which may or may not have different parameters that can be set.

Tony