Vaillant ecoTEC pro 28 combi Boiler advice?

bery_451

Ok coming back to this thread lets analyse:

Max power of my boiler is 26kw

7 existing radiators + 5 new radiators = 11 radiators total.

12 x 1.5 kw= 18 kw

3 sinks, 1 thermo shower, 1 bath, what about washing machine?

Ok to clarify, no matter how big or powerful the gas combi boiler is it can only cope with 1 hot water tap at a time at a good flow rate?

Does the bigger size of the radiators require more power?

Ok from the calculations above and also we choose to use hot water once at a time or use 2 hot taps sometimes, now the question is my current boiler is powerful enough?

bery_451

Bump, any advice

Alex1983

All combi's are one tap operation, some models with a small storage tank inside could supply upto 20litres a minute but they are very rare and expensive.

Bigger rads will use more kw's but averaging all rads at 1.5kw should be fine, unless you have 11 very big rads.

Your boiler would be ok to supply what you need and 1 tap, if you turn a 2nd tap on you will either both get luke warm water or a real slow flow at both and possible scolding hot water.

qsk

bery_451 wrote: »

7 existing radiators + 5 new radiators = 11 radiators total.

Who is your maths teacher, by the way?

bery_451 wrote: »

3 sinks, 1 thermo shower, 1 bath, what about washing machine?

Despite of hype, Combi is a bit too far stretched for a family. As Alex said, it can only supply one tap. That means you needs to schedule your usage strictly. When someone is doing washup, there will no heating, no shower...

bery_451

qsk wrote: »

Who is your maths teacher, by the way?

Despite of hype, Combi is a bit too far stretched for a family. As Alex said, it can only supply one tap. That means you needs to schedule your usage strictly. When someone is doing washup, there will no heating, no shower...

Ok typo has been corrected.

You mean combi boiler cant heat radiators when someone is using a hot tap?

bery_451

Alex1983 wrote: »

All combi's are one tap operation, some models with a small storage tank inside could supply upto 20litres a minute but they are very rare and expensive.

Bigger rads will use more kw's but averaging all rads at 1.5kw should be fine, unless you have 11 very big rads.

Your boiler would be ok to supply what you need and 1 tap, if you turn a 2nd tap on you will either both get luke warm water or a real slow flow at both and possible scolding hot water.

Ok from that 26kw max power of my boiler and considering that a hot tap takes 3kw then I have around 23kw power left for the 11-12 radiators to play around with and 1 hot tap on simultaneously?

bris

bery_451 wrote: »

Ok typo has been corrected.

You mean combi boiler cant heat radiators when someone is using a hot tap?

When the heating is on and you run a hot tap the diverter sends the flow of water to the hot taps instead so yes it does temporarily divert from the heating.


Because the need for hot water is relatively short though you will never notice this as it switches back to heating when the hot tap is off.


The boiler will run the radiators no problem but I guarantee you, you will have hot water issues when, in family life, you try to run hot water in unison with someone else.


If you can live with it then fine.


Washing machines no longer draw from the hot water outlet now so unless your machine is ancient it will only be fed from the cold mains.

roddydogs

It will affect the hot water supply, though especiall if you happen to be in the shower, as will flushing the loo or say a dishwasher.

bery_451

Ok understood many thanks. I be sure to come back here if I need further help.

landlordharrow

Hello guys,

Could someone advise.

Is this a good boiler for a 3 bedroom or a 4 bedroom house? 1 bathroom and 2 bathrooms.

I've got a new boiler replacement quote, supply and fit Vaillant ecoTEC pro 28 @ £2050.

Is this good? I googles Vaillant ecoTEC pro 28 reviews and seems this is a good boiler.