Worcester Bosch 25i vs 30i ?

Adly812

£100 more for the 30i, I've been quoted. I have a two bed, one bathroom home. I live alone and hardly use any gas or hot water... Do I need a 30in? Or will the 25i be adequate.
Is it just the hot water output the difference ? As for £100 extra I'm like just get the 30i, but shall I just save the £100 and be fine for a 25i?

bridgedino

25i will be adequate

Alex1983

30 will give you a better hot water flow rate, I think it's around 14 litres per minute for the 30 and around 12 for the 25

thescouselander

Suggest measuring the water flow rate and sizing the boiler to match. 25kw isn't really that much and will only heat a relitively slow flow of water.

We've got 36kw boiler in our house and it can heat the water to 60 degrees with the taps wide open.

daveyjp

Smb3088 wrote: »

£100 more for the 30i, I've been quoted. I have a two bed, one bathroom home. I live alone and hardly use any gas or hot water... Do I need a 30in? Or will the 25i be adequate.
Is it just the hot water output the difference ? As for £100 extra I'm like just get the 30i, but shall I just save the £100 and be fine for a 25i?

Your gas engineer should be the one advising you once the pre installation survey is completed. The boiler should be matched to the cold water flow rate.

ic

Extra umph will make a difference when the incoming supply is colder in the winter.

JSF

Hi

so what is best as I have a similar decision?

One installer says a 30kw will do a 36kw will give a faster flow but might be overkill.

I dont put my taps on full (else will get splashed) and trying to measure the flow with a litre jug suggests I have at least 14 litres a min on full and that seems fast enough

The 30i however will give 10.7 litres a min with 40 degree increase.

Sorry if thiis sounds stupid .. but

... does the boiler slow down the flow rate from 14 or more to 10.7 and then pass it onto the hot tap at that rate or do i have to make sure I turn the tap to that flow rate?.

Its not as if you can try each one and then install

Alex1983

Not the temperature will very with flow rate. Faster flow low temperature, slower flow higher temperature.