Larger Boiler = Better ?

[tvoburner]

I am going to replace my present combi which has an output of 24kw and I was wondering if there was anything to gain by putting in a boiler of a larger capacity say 28kw. Will it make it quicker filling a bath or is it just a waste of money.

There is just the wife and I in a modern 2 bed semi with 5 radiators to run.

Thanks in advance.

 

[kevplumb]

wouldnt think so
wont get any faster water flow than you have

 

[PEDANTICVINDICTIVEMAN]

A 28kw combi should have a faster flow rate to the hot taps than a 24kw, as long as the incoming cold main is up to it, Example 24Cdi 11.8 ltrsmin 28Cdi 13.5Ltrsmin 35Cdi 16.8ltrsmin all at 40deg temp rise, go for a 28kw if the gas and water are up to it.

 

[ChrisR]

I reckon's PVM's flow figuresa are for 30 degree rise not 40.

Yes go for 28kW. Unless your water supply is dire I expect you will notice a difference. You don't have to have a fantastic supply pressure/flow to see it, cos you fill your bath at about 45 degrees. To be that hot the flow is relatively low. Many boilers restrict the flow down to say 10 litres/min on a 28kW boiler so that you do get sufficiently hot water in the winter when the mains is colder. Vaillant and Worcs do that.

 

[PEDANTICVINDICTIVEMAN]

Sorry I looked at the wrong line in the manual,it is 30deg temp rise as ChrisR says

 

[tvoburner]

That`s great because I`ve just seen an offer on a worcester bosch 28i including clock/flue/filling loop/vat and delivery for £599.99.

Thanks again for your speedy replies.

 

[Just_back_from_the_pub]

Is this attractive price by any chance linked to the fact that it is a non-condensing boiler and therefore an unsaleable item after April 2005? Presumably we will start to see quite alot of boilers of this type advertised at very good prices in view of their shelf-life? Might really be worth going for one of these in view of the perceived problems the plumbing industry is anticipating with condensers.

 

[tvoburner]

Well I`ve got to get a new boiler as my Alpha combi has just packed up and I thought that I would be better off buying something that was tried and tested. The things that I`ve heard about condensing boilers on this forum and elsewhere have kinda put me off. I figure that the next time my combi needs replacing they will have hopefully sorted any problems out with the condensing type.

 

[blahblah]

Far from unsaleable I reckon. No restriction on who they're sold to so DIY and unregistered installers will have a field day. Imagine how much they'll be able to under cut the rule abiders. Also sub class a will still be allowed if condensing impractical to fit. So look forward to a price rise on non condensers later on.

 

[Just_back_from_the_pub]

Wow, that is amazing! I thought that the cpc (compulsion for condensing) was right across the board ie any every boiler had to be a condenser. It seems totally bizarre that non-regs and DIY'ers can instal what the **** they wish completely impervious to gov decree. Must say I have a lot of sympathy with the registered folk on this one! Learn something everyday. Thanks Blah!