Going mad about system boiler efficiency - HELP!

[ShaunCorbs]

Or with a 28mm 2 port head

 

[Knappers]

I like weather comp, what I'd really like is a weather comp and load comp combo.
The whole this boiler/that boiler argument isn't really where I wanted to go but I do see the value in Main boilers as I do 10 year warranty (so neither here nor there on that)
I think maybe coming from commercial systems with blending valves, building management systems and air handling units, I'm just a bit frustrated by the domestic market and the lack of transparency on how things actually work.
I'm sceptical about the terms 'smart' and 'Opentherm compatible' and am unclear on what it takes to call a controller Openthem?
Just look at the Boiler+ labled controls that weren't, like hive!

 

[Knappers]

Well most customers I fit the Evohome Control system for save around 20% on their bills plus better comfort levels (As in warmer). So no I don't think the £700+ is 'blowing' it on controls. In fact most cases you can recoup the costs in 5 years and that's without using Opentherm.

Vaillant don't do Opentherm. I'd have a Main any day over the Ideal. Viessmann took Opentherm off their new Heat Only boiler. Worcester doesn't do Opentherm either. The Main System is the same boiler as the Baxi 800 flagship boiler. So why pay another £600/700 for an extra 5 year warranty and filter? System boiler there's minimal to go wrong in 10 years IMO.

If you're wanting to do HW Priority it's easily achievable on any system even with simple controls with a simple relay. You don't need out fancy.

Weather comp IMO is a waste of time, mainly because it all depends on your insulation levels.

What I want to do is have HW Priority with dual rate on boiler while keeping a standard 2 pipe system, so I can keep load/weather comp.

I don't get the insulation thing, all your weather comp should do is limit max flow temps to keep boiler condensing as much as pos, and I'd assume there would always be some kind of curve setting hidden somewhere in the menu?

 

[Knappers]

I've just caught up with thread from the other week and might have a look at EPH controls as suggested.

 

[ShaunCorbs]

What I want to do is have HW Priority with dual rate on boiler while keeping a standard 2 pipe system, so I can keep load/weather comp.

I don't get the insulation thing, all your weather comp should do is limit max flow temps to keep boiler condensing as much as pos, and I'd assume there would always be some kind of curve setting hidden somewhere in the menu?

Ideal logic has two switch inputs I believe

 

[Knappers]

Ideal logic has two switch inputs I believe

Thanks Shaun. Really don't like Ideal tho.
I swear I'm not being intentionally awkward.
I might go for intergas but never fitted one before (have you/what do you think of them?), or look for controls to do it on baxi/worcester - like evohome (without trv's).
I really liked my (now old and clunkey) vaillant VRC 430 for functionality - like it has legionella/pasturising cycle and actually came with a full manual!

 

[ShaunCorbs]

tbh us as engineer have gone lazy / not needing tech controls like in the commercial game you think what a standard dom house requires with combi or heat just standard on or off if you can get you hand on an old Viessmann you can do what you want eg wc with internal room influence etc

 

[ShaunCorbs]

Have a look at the 200e from Viessmann’s I think that’s compatible with the new version

 

[Knappers]

I did fit a Viessmann 200-w a few months back but with vicare, which just had a room sensor and adjustable curve on boiler. lack of thermostatic control inside was a step too far for customer to get their head around and ended up swapping it out for 3rd party controls.
Did say they're bringing out a 200e type control for vicare wifi system and I'll prob be all over that when they do.
Currently I like worcester as a complete system inc controls (I like matching boiler & control) but this system boiler efficiency hole is bothering me.
There definitely was a clear split for a while before legislation prompted the rush to dumb down efficient controls. To be fair tho I couldn't sell good controls 10 years ago and now everyone wants 'smart' controls. So I don't know perhaps it's all good...?