Unvented cylinder and Combi Boiler

[JAY123]

HI guys

We currently have an Glowworm Ultracom 38CXI. It currently serves 3 bedrooms and 2 bathrooms, one with an electric shower, the other with a thermostatic shower mixer. Our house has 17 radiators (it is a fairly large house). We are planning to add an extension to the house, it will be a total of 5 bedrooms and 4 bathrooms once complete. We have been told by one plumber that we can add an indirect unvented cylinder to our current combi boiler upstairs that can serve the bathrooms, is this correct?Would this be sufficient? Do you think the boiler is powerful enough for all the radiators, as once the extension is complete there could be up to 22 radiators.

Any advice would be much appreciated.

Jay.

 

[gmartine]

Yes and yes. Even if the combined loads of HW and CH exceeded that of the boiler which I doubt the HW cylinder can be timed to heat at time when there is less load on the boiler, say very very early morning.

 

[JAY123]

Cheers mate.

Any recommendation on which cylinder we should get?

 

[ShaunCorbs]

Tbh as it’s not a new ish boiler over 10 years I would factor in a replacement

also I bet the pump won’t be strong enough for 22 rads

 

[Timmy D]

With 4 bathrooms, I’d also be looking to add a mains water pumped accumulator to increase the available water during multiple bathroom usage.

 

[gmartine]

Cheers mate.

Any recommendation on which cylinder we should get?

A very large one.

Everybody has their favorites, do a search on here and youll see.

 

[Timmy D]

A very large one.

Everybody has their favorites, do a search on here and youll see.

As above. Honestly, let the installer give you a couple of recommendations as they will likely be servicing it and may have contacts for that particular brand to assist, in the case of break down.

 

[JAY123]

Cheers guys.

So yes, I think I will be sticking to the Gloworm Ultracom 38CXI Combi we have already and getting a Megaflo 250l upstairs which will serve the possible 4 bathrooms that we will be having.

Is there anything else I need do you think?

 

[ShaunCorbs]

300ls if your doing 4 bathrooms