Boiler central heating dial

quattros

Hi all I was wondering I have 2 control dials on my boiler one for CH and other for the taps temperatures , Now question is the CH where should that Dial be set , A friend of mine said to Max so that the rads get hotter and quicker is this correct at the moment it’s is set around half way mark.

grumbler

quattros said:

A friend of mine said to Max so that the rads get hotter and quicker is this correct

Quicker - this is correct. It's pure physics.

Whether to set to max or not is up to you.

quattros

grumbler said:

quattros said:

A friend of mine said to Max so that the rads get hotter and quicker is this correct

Quicker - this is correct. It's pure physics.

Whether to set to max or not is up to you.

Hi thanks for the reply , So having it set on Max I guess the rads get much hotter And reach temperature quicker so the boiler is tripped out by the stat and not on all the time meaning less energy usage?

Jeepers_Creepers

Make and model of boiler?

There are slight pros and cons. The cooler you have the CH water going out, the cooler it will return, and that means a bit more efficiency when it's a modern 'HE' condensing boiler (it's the cooler return water which condenses the moisture out of the flue gas, grabbing its energy in the process).

However, a cooler flow also means the rads will take longer to get your house up to temp and, in winter, having it too cool could mean the boiler keeps running 'cos it can't get the house up to temp at all. 

Too hot a flow could mean that the boiler cannot shift the very hot water fast enough, so it then has to modulate down to reduce its output and even cycle on and off at times.

So the ideal situation is to have the boiler set to a level where it gets your house up to temp fairly quickly - say a half hour - but not any higher. In practice this will mean a higher setting for Winter, and lower for Summer. Many modern boiler models have the facility to add weather compensation using an external temp sensor, and this will set that output control appropriately - and as low as it can get away with.

Also, the lower you have the running temp of the boiler, the less stress it'll experience. Full on, it'll be delivering water at 80+oC  - that's a lot of continuous heat to have to cope with.

verybigchris

My boiler has a little "e" marked on the dial, at about 80% temperature, which is supposed to be the most efficient setting.

quattros

Jeepers_Creepers said:

Make and model of boiler?

There are slight pros and cons. The cooler you have the CH water going out, the cooler it will return, and that means a bit more efficiency when it's a modern 'HE' condensing boiler (it's the cooler return water which condenses the moisture out of the flue gas, grabbing its energy in the process).

However, a cooler flow also means the rads will take longer to get your house up to temp and, in winter, having it too cool could mean the boiler keeps running 'cos it can't get the house up to temp at all. 

Too hot a flow could mean that the boiler cannot shift the very hot water fast enough, so it then has to modulate down to reduce its output and even cycle on and off at times.

So the ideal situation is to have the boiler set to a level where it gets your house up to temp fairly quickly - say a half hour - but not any higher. In practice this will mean a higher setting for Winter, and lower for Summer. Many modern boiler models have the facility to add weather compensation using an external temp sensor, and this will set that output control appropriately - and as low as it can get away with.

Also, the lower you have the running temp of the boiler, the less stress it'll experience. Full on, it'll be delivering water at 80+oC  - that's a lot of continuous heat to have to cope with.

Hi thanks for your Reply The  Boiler is a Baxi 105E combi. It’s some years old now . As it does have a Digital read out hard to see when turning the Dial what temperature it is set at .

grumbler

quattros said:

grumbler said:

quattros said:

A friend of mine said to Max so that the rads get hotter and quicker is this correct

Quicker - this is correct. It's pure physics.

Whether to set to max or not is up to you.

So having it set on Max I guess the rads get much hotter And reach temperature quicker so the boiler is tripped out by the stat and not on all the time meaning less energy usage?

Hotter - yes. Quicker - no. It takes boiler more tame to heat the same amount of water to higher temperature. But, at the end of the day, the air will reach the set temperature faster.

The amount of energy can be a little higher, not much.

Jeepers_Creepers

Doesn't it has a series of lights on the front panel to indicate temp? Seems it's adjustable between around 35oC and 85oC.

Anyhoo, set it at a temp that makes your system work well - heat up your home adequately fast - but no higher. In warmer months when it's likely only to come on during the coolest parts of an evening, turn it down lower. It's very scientific :-)

quattros

Jeepers_Creepers said:

Doesn't it has a series of lights on the front panel to indicate temp? Seems it's adjustable between around 35oC and 85oC.

Anyhoo, set it at a temp that makes your system work well - heat up your home adequately fast - but no higher. In warmer months when it's likely only to come on during the coolest parts of an evening, turn it down lower. It's very scientific :-)

Hi yes infact it does have a series of LEDs but I don’t think they light up when turning the dial on their own only when system is running up to temp , So i will have to try and set it when the heating is on , What sort of Temperature should the CH be set at ideally ?

chrisw

Bear in mind that a radiator at 80 degrees will be extremely hot to touch and could cause burns if in skin contact for more than a few seconds.

Jeepers_Creepers

quattros said:

Jeepers_Creepers said:

Doesn't it has a series of lights on the front panel to indicate temp? Seems it's adjustable between around 35oC and 85oC.

Anyhoo, set it at a temp that makes your system work well - heat up your home adequately fast - but no higher. In warmer months when it's likely only to come on during the coolest parts of an evening, turn it down lower. It's very scientific :-)

Hi yes infact it does have a series of LEDs but I don’t think they light up when turning the dial on their own only when system is running up to temp , So i will have to try and set it when the heating is on , What sort of Temperature should the CH be set at ideally ?

As low as possible that still works :-)

1) When do you turn up your heating in the mornings?

2) And from what overnight temp to what 'morning' temp?

3) And how long does it take to get to that comfy morning temp?