Upgrade boiler or install unvented cylinder

[Jthomas]

We've recently had a biggish extension added to the house and now have 4 bed with 3 bathrooms. The current (not so old) combi will struggle with the extra demand so was contemplating getting an unvented cylinder to supply the bathrooms but having perused various sites I'm in at least 2 minds on this.

I'm wondering if a storage combi would be better

Any advice? What's the relative cost of adding a cylinder compared to upgrading the boiler?

thanks

JT

 

[Aquaheat]

Firstly you need to know your flow rate and pressure.

A combi boiler in that situation is a definite no no.

Depends on the size of the runs but consider an unvented with a secondary return. Best of both worlds then. Mains hot water and pretty much instant from all hot water outlets.

Cant really put a price on it as there's too many variables but you would never be satisfied running 3 bathrooms a kitchen, other appliances from a combi.

Jon

 

[polesapart]

Unvented. Will require min 22mm supply.

You could leave one or two draw-offs on the existing combi, which is likely to have the spare capacity for the additional heating load.

Your G3 qualified installer can advise.

 

[Jthomas]

Thanks - seems like the unvented cylinder may be the way to go, the plumber we're using has recommended it, he's planning on leaving one draw-off on existing combi.