To Drain or Keep Running

[DIYWell]

I shall be abandoning my late mother's house for 6 months. I'm in the process of clearing it, but it is taking an age and I have little time I can dedicate to the task just now. It's also 300+ miles away so dropping by for a weekend is impractical.

There is empty property insurance in place. There is a lovely condition in it that that says between November and May, either drain the CH or leave the heating running at 12 °C 24/7.

Almost two years ago we had the ancient conventional boiler replaced with a Vitrodens 100-W fitted. That meant we went from a room thermostat in the hall to a freak of a control system that no one truly understands. The winter of 21/22 cost the thick end of £2k to keep the house at 12 °C. The winter of 22/23, thanks to an ass of a third party servicing firm, the boiler was serviced, turned off, but the system wasn't drained. However, I did return to find a plastic stopend on a mains pipe in the bathroom had popped off. Little damage was done as the water had been turned off at the stopcock but it was a wake-up call.

So now I'm unsure what to do. I'll be damned if I shell out a small fortune to hold the place at 12 °C. I'm reluctant to have the system drained; that wouldn't have prevented the pipe freezing last year.

Any thoughts on a sensible course of action welcome.

 

[Alec_t]

Even if you think you've drained the system completely there can be odd sections of pipe which still hold water and freeze. Don't ask me how I know!
Valves and pumps can occasionally seize if they dry out or are unused for lengthy periods.

 

[Madrab]

I'll be damned if I shell out a small fortune to hold the place at 12 °C. I'm reluctant to have the system drained; that wouldn't have prevented the pipe freezing last year.

Cant have it both ways unfortunately.

As far as the hot and cold water systems are concerned then a drain down at the stop tap will allow the system to be drained/depressurised and then leave the taps open to cater for any residual expansion.

The CH, can also be depressurised and partially drained down but that's just a recipe for corrosion to set in and as suggested, for things to start seizing up..

Can't you get someone to take the house on a short term?

 

[Phigo]

It's also worth noting that your toilet and sink U bends can freeze too, this can be prevented by adding some sort of anti freeze.

 

[DIYWell]

Cant have it both ways unfortunately.

As far as the hot and cold water systems are concerned then a drain down at the stop tap will allow the system to be drained/depressurised and then leave the taps open to cater for any residual expansion.

The CH, can also be depressurised and partially drained down but that's just a recipe for corrosion to set in and as suggested, for things to start seizing up..

Can't you get someone to take the house on a short term?

As far as I can see, there is no mechanism to be able to drain the cold water system.

I recall that last year I turned the water off at the stopcock and left the taps downstairs open to allow for expansion. I can't recall if I left the taps open upstairs. However, even if I did, it would seem the the two capped pipes froze and there wasn't enough expansion space.

I could solve that problem by capping the pipes with valves and opening them when the mains is off.

I'll have a think about a partial drain down. There aren't any three way valves in the system, and the lockshields and TRVs are never touched. The rads are heading for 25 years old so who knows what state they're in.

No chance of getting someone in short term as the place is still full of stuff to sort thanks to a sister who is dragging her heals. If it had been down to me, I'd have had it cleared and on the market in six months. Ok, it would have taken longer, but it would have been done by now.