The heating is officially on is yours?

Astria

SAC2334 said:

I ve cracked but only for four hours in the evening 6.pm to 10 pm .Taking readings from the gas meter at start and finish because I m varying the boiler settings and TRV s to see if it makes any difference. 

I lowered the flow rate from 65 cto 55 c but it does take a long time to heat the main room up . My friend who is a Gas safe engineer says it should nt make any difference but just take longer to heat up. Like a 3000 watt kettle boils a cup faster than a 2000 watt kettle and costs the same amount. 

My 4 evenings so far have cost not far off the same amount using just over 2 metric units / 24 kwh/ £2.50 for four hours .
I m going to increase the flow rate to 60 c to see if its more expensive 

One thing I have to ask: What are you radiators designed to run at? The output of the radiator depends on the delta t which is input temperature versus output temperature. It they were designed for 60c (or even 70c) then running them lower than that can cause them to be less efficient, heat up your room slower and use more gas as a result.

Most current radiators on the market now have a delta T of 50, meaning they are quite happy to run at lower expected boiler temperatures.

If your radiators are Delta 70 then they typically require a boiler temperature of 80c, give a return of 60c for a 70c overall radiator temperature. Delta 50 means they have a overall temperature of 50c.

FreeBear

Astria said:

SAC2334 said:

I ve cracked but only for four hours in the evening 6.pm to 10 pm .Taking readings from the gas meter at start and finish because I m varying the boiler settings and TRV s to see if it makes any difference. 

I lowered the flow rate from 65 cto 55 c but it does take a long time to heat the main room up . My friend who is a Gas safe engineer says it should nt make any difference but just take longer to heat up. Like a 3000 watt kettle boils a cup faster than a 2000 watt kettle and costs the same amount. 

My 4 evenings so far have cost not far off the same amount using just over 2 metric units / 24 kwh/ £2.50 for four hours .
I m going to increase the flow rate to 60 c to see if its more expensive 

One thing I have to ask: What are you radiators designed to run at? The output of the radiator depends on the delta t which is input temperature versus output temperature. It they were designed for 60c (or even 70c) then running them lower than that can cause them to be less efficient, heat up your room slower and use more gas as a result.

Most current radiators on the market now have a delta T of 50, meaning they are quite happy to run at lower expected boiler temperatures.

If your radiators are Delta 70 then they typically require a boiler temperature of 80c, give a return of 60c for a 70c overall radiator temperature. Delta 50 means they have a overall temperature of 50c.

Methinks you are a bit out there.... The "delta t" (Δt) refers to the temperature difference between the hot water and the nominal ambient air temperature. For a typical house, this will be 70°C for the CH hot water and 20°C for the room which gives a Δt of 50°C.

Stelrad explains it a bit better than me - https://www.stelrad.com/news-events/blog/the-importance-of-delta-t-in-calculating-heating-output/

peter3hg

Astria said:

SAC2334 said:

I ve cracked but only for four hours in the evening 6.pm to 10 pm .Taking readings from the gas meter at start and finish because I m varying the boiler settings and TRV s to see if it makes any difference. 

I lowered the flow rate from 65 cto 55 c but it does take a long time to heat the main room up . My friend who is a Gas safe engineer says it should nt make any difference but just take longer to heat up. Like a 3000 watt kettle boils a cup faster than a 2000 watt kettle and costs the same amount. 

My 4 evenings so far have cost not far off the same amount using just over 2 metric units / 24 kwh/ £2.50 for four hours .
I m going to increase the flow rate to 60 c to see if its more expensive 

One thing I have to ask: What are you radiators designed to run at? The output of the radiator depends on the delta t which is input temperature versus output temperature. It they were designed for 60c (or even 70c) then running them lower than that can cause them to be less efficient, heat up your room slower and use more gas as a result.

Most current radiators on the market now have a delta T of 50, meaning they are quite happy to run at lower expected boiler temperatures.

If your radiators are Delta 70 then they typically require a boiler temperature of 80c, give a return of 60c for a 70c overall radiator temperature. Delta 50 means they have a overall temperature of 50c.

This is a bit of a red herring. The delta T rating is part of how the power output is calculated and is important to know when specifying radiators in the first place, but there is no physical difference between a delta T 50 radiator and a delta T 60 radiator. The delta T 60 will just have a roughly 25% higher BTU rating for the same panel size/design.
The radiators will either be big enough to cope with the lower flow rating or they won't, the delta T is irrelevant.

The only realistic way to check what is more efficient is by trying it as SAC2334 is doing. A lower flow temperature might be less efficient if the boiler can't modulate down enough and starts cycling, or if it just can't reach the target temperature. There is also a payoff in terms of lower comfort levels if the lower flow rate takes a long time to heat the space.

Astria

FreeBear said:

Astria said:

SAC2334 said:

I ve cracked but only for four hours in the evening 6.pm to 10 pm .Taking readings from the gas meter at start and finish because I m varying the boiler settings and TRV s to see if it makes any difference. 

I lowered the flow rate from 65 cto 55 c but it does take a long time to heat the main room up . My friend who is a Gas safe engineer says it should nt make any difference but just take longer to heat up. Like a 3000 watt kettle boils a cup faster than a 2000 watt kettle and costs the same amount. 

My 4 evenings so far have cost not far off the same amount using just over 2 metric units / 24 kwh/ £2.50 for four hours .
I m going to increase the flow rate to 60 c to see if its more expensive 

One thing I have to ask: What are you radiators designed to run at? The output of the radiator depends on the delta t which is input temperature versus output temperature. It they were designed for 60c (or even 70c) then running them lower than that can cause them to be less efficient, heat up your room slower and use more gas as a result.

Most current radiators on the market now have a delta T of 50, meaning they are quite happy to run at lower expected boiler temperatures.

If your radiators are Delta 70 then they typically require a boiler temperature of 80c, give a return of 60c for a 70c overall radiator temperature. Delta 50 means they have a overall temperature of 50c.

Methinks you are a bit out there.... The "delta t" (Δt) refers to the temperature difference between the hot water and the nominal ambient air temperature. For a typical house, this will be 70°C for the CH hot water and 20°C for the room which gives a Δt of 50°C.

Stelrad explains it a bit better than me - https://www.stelrad.com/news-events/blog/the-importance-of-delta-t-in-calculating-heating-output/

Yes, and so 80 - 60 = 20c ? (70c expected radiator temperature), or 70 - 50 (60c expected radiator temperature) and so on ?

So if you want to run your boiler output temperature at 55c then you shouldn't be using radiators which are expecting an input of 70c, else you are reducing the rated BTU of the radiator?

SAC2334

Astria said:

FreeBear said:

Astria said:

SAC2334 said:

I ve cracked but only for four hours in the evening 6.pm to 10 pm .Taking readings from the gas meter at start and finish because I m varying the boiler settings and TRV s to see if it makes any difference. 

I lowered the flow rate from 65 cto 55 c but it does take a long time to heat the main room up . My friend who is a Gas safe engineer says it should nt make any difference but just take longer to heat up. Like a 3000 watt kettle boils a cup faster than a 2000 watt kettle and costs the same amount. 

My 4 evenings so far have cost not far off the same amount using just over 2 metric units / 24 kwh/ £2.50 for four hours .
I m going to increase the flow rate to 60 c to see if its more expensive 

One thing I have to ask: What are you radiators designed to run at? The output of the radiator depends on the delta t which is input temperature versus output temperature. It they were designed for 60c (or even 70c) then running them lower than that can cause them to be less efficient, heat up your room slower and use more gas as a result.

Most current radiators on the market now have a delta T of 50, meaning they are quite happy to run at lower expected boiler temperatures.

If your radiators are Delta 70 then they typically require a boiler temperature of 80c, give a return of 60c for a 70c overall radiator temperature. Delta 50 means they have a overall temperature of 50c.

Methinks you are a bit out there.... The "delta t" (Δt) refers to the temperature difference between the hot water and the nominal ambient air temperature. For a typical house, this will be 70°C for the CH hot water and 20°C for the room which gives a Δt of 50°C.

Stelrad explains it a bit better than me - https://www.stelrad.com/news-events/blog/the-importance-of-delta-t-in-calculating-heating-output/

Yes, and so 80 - 60 = 20c ? (70c expected radiator temperature), or 70 - 50 (60c expected radiator temperature) and so on ?

So if you want to run your boiler output temperature at 55c then you shouldn't be using radiators which are expecting an input of 70c, else you are reducing the rated BTU of the radiator?

Mine will be the Delta 70 as they are all over 40 years old .
My experiments continue so will increase the CH  flow rate to 60 c and 65 c . The room took too long to warm up and did nt reach my 18 c on my room thermometer and its not even proper winter yet .
Thanks for the info about radiators , something to think about when I replace my boiler .

RelievedSheff

KevinG said:

RelievedSheff said:

Swipe said:

No matter how much I layer up anything less that 13C indoors feels miserable to me. I hate that cold feeling on your face as you walk into a cold room. Funny that I don't get the same feeling when I go outside. Must be psychological. 

I refuse to have a cold house. We want our home to be warm and cosy.

It depends on your definition of cold. The temperature is still nearly 19° with no heating. Is that cold?

In our house yes that would be feeling cold.

RelievedSheff

peter3hg said:

Deleted_User said:

I think I’ll have to check my insulation - heating has kicked on and off for a couple of weeks now with thermostat set at 16.5C

I don’t think internal temperature has been at the 19/20C people here are reporting for a month or so - and I’m in Yorkshire so not the arctic or anything.

Most of the 19/20C people then drop in that they have a log burner. People with a flat with neighbours more generous with the heating might also still be at higher temperatures.

My heating has been kicking in for about a week now but only for roughly 30 minutes in the morning and 30 minutes in the evening using around 10-12kWh a day.

No log burner here and no attached neighbours to share their heat either. Not in a flat.

We just like being warm and cosy at home.

RelievedSheff

Our heating has been doing its own thing all month, coming on and off as needed set by the timer and thermostat.

We have been toasty warm at 20 degrees in the evening with a slightly lower 19 degrees for an hour in the morning while we get up and get ready for work. The rest of the time the house is left at 16 degrees minimum.

Just had our November bill and we have used just under 400kWh compared to 650kWh for the same period last year.

I am genuinely surprised at some of the temperatures some of you live with in your homes. There was an article over the weekend which studied the effects of colder temperatures on the body with surprising results at temperatures higher than those some of you are heating your homes too.

https://www.bbc.co.uk/news/health-63602501

alleycat`

RelievedSheff said:

I am genuinely surprised at some of the temperatures some of you live with in your homes. There was an article over the weekend which studied the effects of colder temperatures on the body with surprising results at temperatures higher than those some of you are heating your homes too.

https://www.bbc.co.uk/news/health-63602501

I wasn't overly impressed with the article in regards to how people live in a house (heated or otherwise).

Whilst it does show how cold causes the body to work harder to maintain a core temperature - the "conditions" it was undertaken in (man sat still in shorts and a half open shirt to allow for sensor attachments) are outside of any sort of "norm".

Alnat1

The guy in that report was in shorts and a T-shirt. Those of us with 18C or less as their target temperature tend to wear a bit more and be happy to use throws.