Ideal Logic+ 35 Vs Vogue 40

[hyperbole]

Another boiler suggestion post. Just want some impartial advise.

4 bed detached house built 20 years ago with cavity wall insulation and double glazing. 1 bathroom and separate ensuite shower. 2 adults and 1 child.

Cold water flow is 20l/m. 16 radiators but 6 are single panel. Already have Tado which supports OpenTherm.

Want to convert gravity fed system to a combi. Primarily to get rid of the airing cupboard which houses the hot water cylinder. We need this space to enlarge the bathroom. Also, prefer on-demand hot water. Fully aware of the disadvantages of the combi.


Getting conflicting information from the gas engineers that came out to quote. Some quote 30kw boilers and say 35kw-40kw is overkill, some say I need to go for 35-40kw.

I am contemplating between these

Ideal Logic+ C35

DHW output 35kw
DHW flow rate 35C rise : 14.5l/m
CH output 70C min/max : 7.1kw -24.2kw
7 year warranty 10 years on heat exchanger

Ideal Logic Vogue Gen2 C40 or Vogue Max C40

DHW output 40kw
DHW flow rate 35C rise : 16.4l/m
CH output 70C min/max : 5.7kw-32.0kw
10 year warranty for Vogue and 12 for Vogue Max.

I think all 3 have stainless steel heat exchangers and support OpenTherm.


I am leaning towards the Vogues as they provide a better flow rate and can modulate to lower CH output so assuming will be cheaper to run?

Are there any major disadvantages with going for 40kw Vogue?
Too much for our needs?
I am happy to pay a bit more and get a really good water output in the shower.
Is 14l/m Vs 16l/m that noticeable?
Or 7l/m Vs 8l/m when running 2 showers or taps at the same time (not very often).

Thanks in advance.

 

[vulcancontinental]

Nice to see an enquiry from someone who has done a bit of research themselves.

Output is for hot water and it appears you have enough cold for a 40.

Space heating requirement would be typically 9-10kW at -5°C and 5kW at 10°C

Don't know detail about Ideal models but I think the Logic is ali. Someone who knows more will be able to tell you whether they can be range rated.

If you're generally interested in heat loss and how to optimise a heating system you might be interested in a webinar Heating Efficiency and Optimisation. From a different manufacturer but not sales at all, it's for public and installer.
Use the link to register. If it will not let you sign on without a GS registration number ring 01727 744002, they'll sort it.

https://carrier.zoom.us/webinar/register/2215979244261/WN_MvmjBYumR9eZlwYEkcujEw

 

[Madrab]

The increased input for the combi is primarily to deliver more L/Min of HW. As far as input for radiators is concerned then with the number of rads you have it's not really a consideration, any of those would be more than enough. Even then you would want a boiler that can modulate as low as possible as far as space heating is concerned.

HW requirements should be the main driver and yes, going to a combi is madness if you have a full household IMO.

Don't forget the figure the boiler man's quote is a targeted ideal and usually on the bench at a 35deg rise, real world figures may not be the same especially in the winter where the cold water is colder. There are other factors that come into play too dynamic pressure not just flow, shower types, flow through pipework/showers, distance HW has to travel etc. I would carefully consider things before removing the cylinder.

Not sure you would get too many Ideal fans here either, unfortunately they wouldn't be at the top of my list.

The logic's are all alloy HEX's but the vogue's are S/S if I remember rightly.

 

[MeldrewsMate]

I am pleased see that you've chosen a British made boiler.
As above with regard to the outputs, as low an output as possible (high turndown ratio) on heating, as high as possible on hot water production.
The Logic has an alloy heat exchanger, the Vogue's is stainless steel.
The Logic's 7 year warranty will be extended to 10 years if you buy the 'Max' version; it includes a magnetic system water filter. Likewise, IIRC, the Vogue will go to 12 years as a 'Max' variant. Don't get too hung up over the length of the warranties though; all manufacturers seem to add conditions that could easily be used to wriggle out in later years!

Some other things to consider both now and in the near future:-
1. Gas supply - you will probably have to increase the bore of your gas pipework to feed this more powerful boiler.
2. Interaction - the hot water flow to a shower may be excessively disturbed as other water outlets are put into and taken out of use.
3. COP26 - if we are forced to go the heat pump route a cylinder will be the only practical way to produce hot water. If you must remove the old cylinder then start planning for where the new one will go!...in general terms, keep your options open.

MM

 

[vulcancontinental]

A couple of caveats to posts above. The figures will be achievable for hot water, if you've enough gas and water a clean boiler will deliver the said flow rate 35°C hotter than the temperature of the cold entering the boiler summer or winter, it's just the incoming water will be colder in the winter so the achievable hot temperature will be lower unless you reduce the flow rate. There's a lot of sense in retaining the hot water cylinder for performance or planning for the future. Think about a boiler that can control a heat pump, solar thermal, solar PV and dual flow temps if you do reconsider a combi. Just one thing, you're not considering a combi in the loft I hope, to locate on so far from the tap you use most isn't good practice I believe (just my sixpennyworth).

The Ideals are as far as I know are assembled in the UK however the Vogue small bore main exchanger is French, the fan German, the water block Italian, the plate heat exchanger Italian and if it's the Logic, the cast aluminium heat exchanger Chinese as will be the thermistors and possibly the wring loom although that might be Italian also. Ideal is part of the Atlantic Group, a French company but they, like Vaillant,(German) Viessmann (German) Baxi (Netherlands) Worcester (German) Vokera (Italian) Glow Worm (German) Intergas (American) Main (Netherlands) all employ Brits. Google can tell you roughly how many each employ if that's important.

 

[DP]

You cannot go wrong with vogue. second choice would be Logic

 

[muggles]

I am pleased see that you've chosen a British made boiler.

Hardly British made. Assembled here, yes, but the components are all manufactured overseas and Ideal themselves are owned by a French company.

@hyperbole out of those two I'd go for the Vogue every time. Logics have had a lot of issues and I'm yet to be convinced they're fully resolved

 

[MeldrewsMate]

Hardly British made. Assembled here, yes, but the components are all manufactured overseas and Ideal themselves are owned by a French company.

Whilst there are always those who will argue that the copper in their British made cable is mined overseas there remains the inalienable fact that a boiler assembled in Britain will have created more jobs in Britain than one assembled overseas. Yes, it would be far better to have all components mined, processed, and manufactured here too, however as a consumer of these products, and one who is keen to keep skills and jobs in this country, the best I can do is to buy that which is assembled here, and try to encourage the manufacturer to increase their British content.
I don't care who owns the company, just that they provide employment here. Our buying choices today determine where our children's jobs will be tomorrow.