ideal vogue 32kw or viessmann 36kw boiler?

[JonHeath]

Hi all,

My brother in law has had several quotes for replacing his boiler and hot water cylinder.

It's a 4 bed house with 12 radiators.

One guy has quoted that he'll use an ideal vogue 32kw boiler with 210l unvented cylinder.

Another has quoted he'll use a viessmann 36kw boiler with a 300l unvented cylinder.

Can anyone provide any experience or advice on the specs of these quotes? Are these decent boilers?

Many thanks
Jon

 

[Dan Robinson]

Wouldn't use either.


He almost certainly doesn't need 32kW either.


Intergas sb24 with a 21 litre cylinder would be plenty I would wager.

A far better proposition than the Ideal ****box anyway.

 

[Classic40]

Ideal Vogue does get a good write up and comes with a 10 year warranty (Not sure if the warranty is worth the paper its written on however).

 

[D_Hailsham]

Forget brands for the moment; let's get the basics right first.

A four bed house with 12 rads will not need more than about 18kW to heat it. You can find out what it actually needs by using the Whole House Boiler Size Calculator.

That includes a 2kW allowance for the HW cylinder. More about that later.

Both quotes suggest an unvented cylinder. Did the potential installers measure the flow rate and dynamic pressure? If not, how do they know an unvented cylinder is suitable? As for the size of cylinder, how many bath and showers are there which could be used at the same time?

You need at least 20 litres/min for an unvented cylinder. You can check this at the garden tap using a marked bucket and a watch. Repeat, at the garden tap, when the cold tap in the kitchen is fully open. The smaller the drop in flow the better the pressure.

Now about the hot water allowance. Modern fast recovery cylinders can absorb about 22kW and take about 20 minutes to reheat a cylinder after 70% of the water has been used. Because of the short recovery time hot water priority is normally recommended, i.e all the boiler output is used to heat/reheat the cylinder; central heating is stopped while this happens. This means you only have to install a boiler suitable for the maximum requirement, heating or hot water, not the sum of the two, which is what the installers have done.

 

[newbuildinstaller]

Intergas sb24 with a 21 litre cylinder would be plenty I would wager.

I would wager poss 189l more!

 

[Agile]

Intergas sb24 with a 21 litre cylinder would be plenty I would wager.

I was also wondering how much the wager was for !

 

[Agile]

As far as the power is concerned I am sure that 18 kW is most likely to be enough although not criticise any fitting a 24 kW boiler.

It needs the power outputs of all the rads added together and then 2 kW for water heating.

Tony

 

[JonHeath]

Thanks for the replies.

The house is very large and will be extended to 5 bedroom in the near future. A number of the radiators are large too.

In terms of showers, there's currently one shower off a pump and one is electric. These could be on together. There's also a bath and potentially a new ensuite in the future.

Any other opinions on the brands quoted?

Cheers
Jon

 

[Dan Robinson]

I allowed 24kW in case of it being a largish property or oop North where it might be chilly.

I was also meaning 210 litre cylinder .

OP.

Our installation menu is as follows - in order of preference based on actually experience rather than incentives and spangley brochures.


Intergas
Atag
Vaillant if you have to have a brand.

All have 5 year warranty - although rumour has it the Intergas is soon to be extended. Vaillant has 7 years if done by an approved installer.

Veissman are OK as long as it is the 200 series.


Ideal? I would rather heat my house with candles.

 

[BigSnoopy01]

avoid vaillant unless you want your customer to be stolen from you.