richman wrote:

The vaillant is nearly new and I wonder if some clever internal
rearrangement will turn it into a sealed system boiler or should I just
bite the bullet and buy a new proper one.

What do you reckon?

There is nothing to stop you using the combi just like a coventional
boiler with water heating driven (via zone valves etc) from the CH side
of it.

You could then either not use its DHW capability at all, or more
probably use it either for one of the showers (where it should work well
with no other demands on it to upset things), or perhaps things like
just feeding the kitchen where the (probably) shorter distance to the
taps would save having to run off so much before getting hot water.

--
Cheers,

John.

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