Boiler Thermostat Setting

[bcfcjwb1]

Hi,

During the current cold snap, our heating system has struggled to get up to temperature!

I've had a think about what has changed since last winter, and I've remembered that the fan in our boiler (Ideal Classic) was replaced in October. I'm now wondering if the engineer adjusted the thermostat on the boiler at the same time.

The gauge in 1 - 6 and it was set to just over 2. I moved it to just over 3 and the difference is amazing - can someone please advise what I should set this to permanently?

Thanks in advance

 

[bhm1712]

set it so that the temperature you set your room stat to is achieved, and so that you are comfortable,there is no set rule. if you have no stat just set the boiler so that the house temp is as you like it.

 

[mogget]

Also make sure it's not so cool that the cylinder stat never clicks off!

 

[DP]

Of course there is a rule as to what the boiler stat should be set at.

Radiator is sized for heat lost from the room where said radiator is fitted. That room would have a design temperature (e.g. lounge has a design temperature of 20 degrees C). Room heat loss is calculated (not guessed) with outside temperature of -1 degree C. Therefore, 21 degrees of heat is lost from the lounge to outside and some heat to other areas. Total heat lost is equal to the size of the radiator which will keep the lounge at 20 degrees C (with outside at -1) when boiler delivers 85 degrees (used to be 85) of primary water temperature which is setting 6.

As external temperature rises, boiler thermostat can be adjusted to lower settings. Setting of 6 also gives you possible 85 degrees of hot water if no controls exist on HW cylinder. This is normal (but undesirable) for nil control gravity HW circuits.

For full controls (plan S or Y) I would run the boiler on setting 6, unless the boiler is condensing, where it becomes a little tricky trying to eek out max efficiency with variable freezing conditions we are having at the moment. Condensing boilers are efficient at lower setting of boiler thermostat.

 

[bcfcjwb1]

I'm not sure I really understand the replies, so I thought I'd post a few details about my system...

It's a Megaflow system, with a Heatmiser digital thermostat.

Most radiators have thermostats on them.

Thanks

 

[David937]

Seeing that you have a hot water cylinder set the boiler at setting 5 or 6.

 

[hect]

Set stat to max/nearly max - systems are balanced as per rad heat of 82 deg.....
Dont use boiler stat to control heat - that should be done through room stat!

 

[oilman]

Set stat to max/nearly max

That way you can get the heat exchanger scaling up fastest and thus allow you to get a new boiler quicker.

- systems are balanced as per rad heat of 82 deg.....

From what I've seen, most systems aren't balanced.

 

[hect]

If systems aint balanced thats down to engs then, not boiler manufacturers!!

If evidence of scaling, fit inline scale reducer then!!!

 

[mogget]

If evidence of scaling, fit inline scale reducer then!!!

In the heating circuit?

I've never heard of that before, could you explain?

 

[simond]

Thermostat on boiler should be up near max in very cold conditions, down lower in mild weather.

It's a bit trial and error, as there are lots of variables which all revolve around your house insulation values and the sizes of the radiators, rather than the boiler.

 

[hect]

If evidence of scaling, fit inline scale reducer then!!!

In the heating circuit?

I've never heard of that before, could you explain?

Apologies - I meant one of those magnetic vents similar to a spirovent

 

[mogget]

Apologies - I meant one of those magnetic vents similar to a spirovent

OK, thanks - I did wonder about that one

 

[bcfcjwb1]

Thanks for the replies everyone, I've now set it to 4 and am very happy with the outcome.

I've had to lower the setting on the thermostatic valves on a few radiators to keep the house at a similar temperature throughout!