Combi boilers

[sandra Davie]

Can a combi boiler be installed in the original cupboard which does not have an outside wall

[CheekyChops]

Yes - my combi boiler isn't on an outside wall, it has a vertical flue instead.  My brother had his installed in the airing cupboard where his old hot water tank used to be, again, not on an outside wall.

[BillyNoMates]

But dependent upon the model, there will be a limitation on the length of the vertical flue.

[Tim B]

Further to bnm's answer, yes there is a limit.  The flues are usually fan-assisted and need to vent over the shortest possible distance.  My solution when fitting in the original airing cupboard was to take it vertically throught the ceiling and the through the roof with a suitable exit (usually supplied) through the tiles.