On Dec 21, 8:26*am, " wrote:
On Dec 21, 8:22*am, " wrote:



I'm about to go away for a few days, and usually I would switch the
central heating thermostat down to the frost setting.

That of course will be sufficient to ensure that the pipework inside
the house won't freeze, but my feed & expansion tank is in the loft -
and with the exceptionally cold weather, I could imagine that might
freeze.

My system is a thermal store (i.e. large volume of water), so hot/cold
cycling actually results in a fair bit of movement of the water level
in the f&e tank. I'm guessing that because it's never off for more
than 8 hours on the current timer settings, that any ice "skin" in the
tank gets broken up by the movements in water level.

So I think I'm going to play safe as temperatures are remaining below
freezing for days - and leave the system on its normal settings.

But I'd like to hear - are f&e tanks freezing a real problem?

Are burst pipes elsewhere in the system (due to inadvertently creating
a "sealed system") a possible outcome?

I should add, the f&e is mounted high on wooden platform on a gable
wall inside the loft - not in contact with the ceiling of the heated
room below. The tank is insulated to all sides and top (but only with
the kit supplied with it - i.e.not that great), and the (copper) pipes
to it well insulated with close fitting climaflex.

Ok - just been up there to check, whilst the water is pretty chilly
(that's the SI value for a bit above freezing) - there's no sign of
ice at all, even after several days of outside temps continuously
below zero.