Combi boiler or combi storage boiler?

sxp842

Hi all

I’m trying to decide between a combi boiler (e.g Viessmann 30kw) and a combi storage boiler (e.g Viessman Vitodens 111-W or Vaillant 938).

We have a 3 bed flat with one bathroom. We currently have a hot water tank which we need to get rid of due to space - the tank takes up about half of the bedroom.

Our only options are a combi boiler. It won’t be as good as the hot water tank, but my main attraction to the combi storage is that it should theoretically allow you to run two hot water taps at the same time. I understand this a problem with standard Combis.

However, the storage combis are huge, as big as a washing machine!

Does anyone have experience of storage combi? Are the benefits of it worth the size, when compared to a normal combi?

Thanks!

Is a combi storage worth it over a normal combi?

Cardew

Many Combi boilers - including the Viessman combi I have installed in an annex - have a small internal storage tank. The purpose is to enable Hot Water to be available faster at a tap. This facility can be switched off.


Obviously this tank is kept at the desired temperature to enable faster delivery of Hot Water; this means that from time to time the boiler will fire up to heat the water. Several people on MSE have commented that noise of the boiler firing up in the middle of the night can be disturbing; and they switch off the facility.



The Viessmann 111w has a 46 litre internal tank, so I suspect the boiler might have to fire up more often to heat a larger tank - unless there is a facility to switch it off at night.