Property Unoccupied Over Winter Months > Central Heating Question

scoot65

bob_a_builder said:

Example clauses from the specialist 'un-occupied' insurance we used 

Regarding the "combustable materials within or outside the property must be removed" clause could be problematic in relation to a furnished property. I'm thinking sofas / easy chirs and beds are all combustable. 

Eldi_Dos

scoot65 said:

The light timers I mentioned were the dial type that you press segments to get the desired timings. Are these what's called electro mechanical? 

That is the type I use ,can be set in 15 minute segments so quite flexible. Gives peace of mind if away for a few days.

Bendy_House

Troytempest said:

We are in the South West and regularly go away for 8 weeks - Jan / Feb.

Heating on for 1 hour morning and 90 minutes evening plus froststat on boiler. Neighbour in once a week and all good. Insurance happy with that.

Nice. So you set your heating to come on as if you were still living there?!

Also in the SW, I've just checked my historic Hive house temps over the past few days (very smug grin on face...) and find that the two zones both drop in temp in a surprisingly linear fashion from mid-evening to a low at around 7 or 8am. From there it starts to climb again, and that would surely be from the outdoor temps warming up, coupled with some direct solar gain.

The weather is still very mild, of course, so in deep mid winter I'd 'expect' the drop to be a lot more severe, and the MIN temp to occur a bit later due to the longer nights, say at around 9am? (all this if no artificial heating provided, of course). And from there, with the outside warming, along with normal solar gain, it would start to rise again.

The point being that your current heatings times are almost perfectly set for when it isn't actually required

So, if you wish to protect your house from massive temp fluctuations, and from the worst of the cold, I'd suggest your heating should be set to come on during the early hours of the morn, and off again at, say, 8am, when you can expect the day to take over. All with a 24hour minimum frost temp protection.

Man, lovin' my Hive

The Hive 'Mini' is cheap. I SOLD a brand new one with receiver for £40. (I'd bought it as part of a full kit which included the Hub and also two Smart bulbs for £60, and sold the other parts (the bulbs went for over £20...), so got the Hub for minus-'free'.

On that note, the App also controls the Smart bulbs, if you have them, so you'd have full scheduled and remote control over 'security' lighting too. 

Surely such a remotely operated controller makes sense if you leave your house unattended? Gives you the ability to monitor temps and react if they plummet for some reason - a deeper frost, or your boiler not working...

FaceHead

Section62 said:

scoot65 said:

The boiler is a 4 years old Intergas ECO RF Combi Compact which is serviced annually. I seem to remember the engineer stating that the boiler has an anti frost system built within it which keeps the internal boiler temp at 5°.

 

I wouldn't leave a combi boiler switched on if the mains water supply is turned off.

Why not? I do this, so am keen to find out why it's a bad idea.

My understanding is that the boiler has access to the mains water via, and only via, the filling loop, which is a little lever under the boiler I can use to top up the pressure. 

If no one is there to operate the lever, surely the boiler doesn't "know" I've actually turned the water off at the meter? 

If I was to go away on a long holiday, I would turn the water off at the meter to guard against a burst cold water pipe, and would leave the boiler on, with the thermostat set to c.10 degrees, so it would kick in if there was a super cold snap to prevent freezing

Bendy_House

FaceHead said:

Section62 said:

scoot65 said:

The boiler is a 4 years old Intergas ECO RF Combi Compact which is serviced annually. I seem to remember the engineer stating that the boiler has an anti frost system built within it which keeps the internal boiler temp at 5°.

 

I wouldn't leave a combi boiler switched on if the mains water supply is turned off.

Why not? I do this, so am keen to find out why it's a bad idea.

My understanding is that the boiler has access to the mains water via, and only via, the filling loop, which is a little lever under the boiler I can use to top up the pressure. 

If no one is there to operate the lever, surely the boiler doesn't "know" I've actually turned the water off at the meter? 

If I was to go away on a long holiday, I would turn the water off at the meter to guard against a burst cold water pipe, and would leave the boiler on, with the thermostat set to c.10 degrees, so it would kick in if there was a super cold snap to prevent freezing

I wondered about that, too. But perhaps S62 was considering the DHW side? Many boilers have a 'pre-heat' setting, so perhaps this could cause problems if the DHW system has been drained? In which case, not draining it might be ok? I dunno.

BUFF

FaceHead said:

Section62 said:

scoot65 said:

The boiler is a 4 years old Intergas ECO RF Combi Compact which is serviced annually. I seem to remember the engineer stating that the boiler has an anti frost system built within it which keeps the internal boiler temp at 5°.

 

I wouldn't leave a combi boiler switched on if the mains water supply is turned off.

Why not? I do this, so am keen to find out why it's a bad idea.

My understanding is that the boiler has access to the mains water via, and only via, the filling loop, which is a little lever under the boiler I can use to top up the pressure. 

How do you think that a combi heats DHW, that water comes off mains & doesn't enter via the filling loop ...?

chris_n

There is no problem turning the water off to a combi without pre heat. There is no way to run the boiler if the flow switch doesn't activate, even if it did fire it would only heat the water in the boiler anyway. When it got to temp it would modulate then turn off. If you have a pre heat you can normally turn it off anyway.

Bendy_House

Thanks BUFF and Chris.

Yes, I understand the combi method - heating the DHW via the P2P. And since with pre-heat the boiler does this repeatedly even when there's no DHW demand at all, there clearly isn't an issue with it running with no flow.

How many folk turn off their combi if they go away for a week? I certainly don't, and (until recently) I had the pre-heat on, and the bludy thing fired up stupid-often, obviously without any issues.

So, if leaving a home unattended which has a combi fitted, I think I'd turn off the mains stopcock, possibly release the pressure from the cold side by turning on the cold kitchen tap for a few seconds, but would not ditto the hot side. I'd then leave the boiler running to do its job, and that's to prevent the house 'freezing'.

Mistral001

Some people have suggested draining the pipes, but surely that means that the inside of the radiators will be wet and also exposed to air and since there will be no through flow of air, moisture will be trapped in the radiators.  Moisture plus air surely is a recipe for accelerating the rusting process.

Apodemus

Mistral001 said:

Some people have suggested draining the pipes, but surely that means that the inside of the radiators will be wet and also exposed to air and since there will be no through flow of air, moisture will be trapped in the radiators.  Moisture plus air surely is a recipe for accelerating the rusting process.

When people talk of draining the pipes, they normally mean the hot and cold water systems, rather than the central heating.  For  the central heating system, it is probably more practical to simply make sure that the system inhibitor is one that also acts as an antifreeze, if there is any risk of the pipes being exposed to low temperatures.