Combi vs Open Vent for 3 Bed family home

[Rob_Quads]

Its come to that time when the boiler is due a change (over 30 year old Fuelsaver 30F). I've had the first company round for quotes (2 more due) but still not sure which way i should be going.

House is 3 bedroom / 1 bathroom / 8 radiator (1 double in livingroom) with an existing Open Vent boiler.

The two options presented are

Worcester 15Ri Boiler + New Cylinder = ~ £300 cheaper as its a straight replacement. Currently have a very noisy shower pump but it works well.

Worcester 30 Si Combi Boiler = More as it requires some rework and gas lines moving etc

Overall I think the Combi would be the more efficient one to be going for BUT I am not sure if its suitable to a house with dishwashers etc where its very likely we are needing a shower when other things like washing machine/dish washer / washing is going on in the evening. Can a Combi really handle this without temperature of the shower being affected?

Going for the combi would get rid of the shower pump which is a good thing but our mixer is not thermostatic so that would also need changing (not the easiest of jobs)

 

[lightning]

http://www.boilerguide.co.uk/articles/what-is-a-combi-boiler

 

[dcawkwell]

If installing a combi I strongly suggest replacing your
shower with an electric shower in case of problems with the boiler.

There is then a backup hot water supply for washing.

I would avoid worcester. Over priced in my opinion.

I suggest going for an unvented cylinder and the smaller
boiler. Then you have the mains pressure hot water for showers.
Immersion heater for backup and a small system boiler.

 

[looneyfitter]

System boiler and unvented cylinder for me. Worcester is pants and way over priced.

Viessmann 200w system with HO1A controller and a 170-200l cylinder. Pressure and flow rates need to be checked either way.

Best of both worlds with this setup

HTH

 

[Rob_Quads]

One of the annoying things about the normal boiler is we would be replacing it in the same location and there is no way of draining it inside so it would need to have an insulated external drain on the end of the house which is a walkway through to the backs of all the gardens round me.

 

[Rob_Quads]

If I went the Combi route then it would be going in the airing cupboard where the existing cylinder is - this is right next to the soil stack so the drain for it could be inside. Not enough room for a cylinder and boiler in the cupboard though.

 

[looneyfitter]

the 222 is the dogs danglies and will fit in most airing cupboards

 

[essexmick]

If I went the Combi route then it would be going in the airing cupboard where the existing cylinder is - this is right next to the soil stack so the drain for it could be inside. Not enough room for a cylinder and boiler in the cupboard though.

Hello Rob Quads,

What did you go for in the end? And how did it work out?

I'm in a similar position to what you were in a few years back and would be interested to hear.

Regards