Do I leave boiler on while away?

Patrick_David

My boiler manual says to leave it on constant with the thermostat set to 15 degrees if going away.  Apparently, it will only kick in if it gets freezing or something.
Tried this last Saturday and it seems to have cost more money than when I am home.  Am I doing something wrong?
I'm heating one room at a time and totally layered up so it seems a waste to have it warmer at home when I am not here. 
 On low income so really can't afford this.  
Any suggestions please?

grumbler

Patrick_David said:

My boiler manual says to leave it on constant with the thermostat set to 15 degrees if going away. 

What thermostat?

Makes no sense to me if it's room thermostat. Makes some sense if it's HW or CH water thermostat in the boiler.

diystarter7

Hi OP

If we have been away for 2/3 nights in winter we always have the thermo on full blast but heating is controlled rd by rad via TVRs
and the one without the TVR is top landing - TVR's turned low so only comes on for a few hours I guess unless very cold.

We look at it like this ie pay possibly or possibly not a few extra quid in heating come back to a warmish home and hopefully no burst pipes.

Thanks

Patrick_David

The room thermostat I presume Grumbler.  I assume the central heating will kick in enough to prevent the pipes freezing.  The only problem I have with it is the flat will be warmer in my ansence than when I'm here.
I don't mind paying a few extra quid but as things are with fuel prices I am constantly afraid I shan't be able to pay my bill on time and they'll end up putting me on one of those prepayment meters.
Thank you both!

macman

It doesn't need to be set as high as 15C. You could leave it on say 10C for the coldest night hours, say 2am to 6am.
But it all depends where your pipe runs are, and to lag them if necessary. It's no good heating the rooms to 15C if you've still got exposed pipework that is near freezing point, in the loft or externally.
Is this a combi system, or do you have a cold water tank? It's normally the latter systems that are vulnerable, with cold water pipes up to and around the loft.

grumbler

Patrick_David said:

The room thermostat I presume Grumbler.  I assume the central heating will kick in enough to prevent the pipes freezing.  The only problem I have with it is the flat will be warmer in my ansence than when I'm here.

Like I said, I presume it's the boiler thermostat.

Frost Protection

Frost protection is a feature of many boilers that prevent the water in the boiler from freezing when subject to low and freezing temperatures. This is a critical method of avoiding any serious damage to your boiler and maintaining functionality.

Typically, across our range of boilers, the frost protection system operates the boiler pump as soon as the heating circuit water temperature falls below 12 degrees centigrade. The pump stops as soon as the temperature of this water reaches 15 degrees centigrade. If the heating system falls below 3 degrees centigrade, the burner ignites. This ensures you do not fall victim to any potential frost, yet still maintains efficiency under normal operation.

 And for a room even 5C is good enough IMO.

ETA: by going away do you mean for a short time, not, say, a holiday?

If so, then 15C is the temperature set in my smart room thermostat 'geofencing' option. Otherwise it takes too long to heat the house when somebody returns to the house. The same temperature is for nights.

However, this has nothing to do with protecting the boiler and the CH system from freezing.

Patrick_David

It's a combi and I don't think there are exposed pipes, it's sheltered housig a flat.  It's owned by the council so I would think they'd have that covered.
I am going to family for about a week at Christmas.
It says here to leave programmer on constant and room thermostat at 15 degrees.  If the temperature with the appliance (it doesn't say which appliance) falls below 8 degrees then the pump will run water to stop freezing and then it'll eventually fire up if gets colder still. 
The bit where it the water circulates at 8 degree and then everything else happens is fine.  I just think it costs a lot of money if the heating comes on at 15 degrees when no-one is here.
Sorry to be so thick.  It's driving me a bit mad trying to weigh it all up.
Thank you for your help. 
Perhaps I should just reduce the room thermostat so it doesn't kick in until say 10 degrees.
Thank you all for your patience!

grumbler

Patrick_David said:

It's a combi and I don't think there are exposed pipes

Just use your common sense then.  Mine says that 5C for a room thermostat is more than safe if it's located not in the warmest part of the house.

diystarter7

Our TVR's have a frost setting but we never put them below 1 (as pin may jam)  unless removing a rad. 

diystarter7

Patrick_David said:

It's a combi and I don't think there are exposed pipes, it's sheltered housig a flat.  It's owned by the council so I would think they'd have that covered.
I am going to family for about a week at Christmas.
It says here to leave programmer on constant and room thermostat at 15 degrees.  If the temperature with the appliance (it doesn't say which appliance) falls below 8 degrees then the pump will run water to stop freezing and then it'll eventually fire up if gets colder still. 
The bit where it the water circulates at 8 degree and then everything else happens is fine.  I just think it costs a lot of money if the heating comes on at 15 degrees when no-one is here.
Sorry to be so thick.  It's driving me a bit mad trying to weigh it all up.
Thank you for your help. 
Perhaps I should just reduce the room thermostat so it doesn't kick in until say 10 degrees.
Thank you all for your patience!

Hi Op
Shelter blocks have comm heating on all of the time ie come lounge and comm areas and that imo keeps the frost away.

Via work when i visited council shelter places, boy was the heat on high, too much heat but possibly all change now.

If you are surrounded by other apartments above, below and to both sides you will get some het from them as I cannot ever recall visiting a cold shelter apartment.

Patrick_David

Just want to thank everyone for their help.  I shall leave it on as instructed but set the room thermostat to 9 degrees.

Merry Christmas!