Central Heating Question

[Endulini]

Hi All,

I have a property that is going to be empty for a while and with the colder weather drawing in I was intending to turn the water off to limit any possibility of water damage. The central heating system is a standard rad based system with a boiler and feeder/expansion tank in the attic - assuming there are no significant leaks is there any danger in leaving the central heating on (albeit slower than if it was lived in) during the winter to keep the house slightly aired? Obviously this will mean that the system won't get topped up when necessary by the ball-c*ck in the attic but how much evapoation does a typical system really have? With no one in the house there will be no alert if the boiler packs up for any reason.

Thanks

[Michael Chare]

I would say that there is a risk that the water in the expansion tank and pipes will freeze. As might any water associated with a cold water tank - if you have one.

[Andrew Gabriel]

My grandmother's house was empty for a couple of years before it was sold. I left the loft hatch open and the room stat on something like 12C, IIRC. Checked up on it every few weeks, and used a saucepan to ladle water from the cold water tank to the expansion tank occasionally (with the water turned off in the road).

When we did turn the water back on, the ballcock turned out to have been damaged by freezing at some point, and I had to replace it.

If we had known at the outset how long it was going to take to sell, I would have fully drained everything down, but we thought viewers would probably want to see a working heating system.

Also check what your insurance cover says. Cover for long periods away in the winter will usually require a full drain down, or heating running at something like 15C 24/7, or no cover for burst pipes and consequential damage.

[dennis]

That's what a £20 frost heater and a zero standing charge tariff is for.

[meow2222]

Sometimes such systems have been fitted with no water feed. A single drop of mineral oil in the header tank should cut the little evaporation.

NT