Is room taking too long to warm up?

[bhm1712]

Comment removed.

 

[D_Hailsham]

The following graph shows how the set temp (red trace) and actual room temp (blue trace) changed over the last 24h:

View attachment 94882

Is the radiator sufficient for the room size?

I'm intrigued by the way the room temperature goes up in steps. The 'treads' are where the boiler goes off for a short while.This could be caused by the thermostat (make and model would help), or by the boiler short cycling (same info please). Eliminating these steps, so the room temperature increased continuously, would reduce considerably the room's heat up time.

As for your question, the fact that the room reaches the desired temperature suggests that the rad is large enough.

 

[garmcqui]

I'm intrigued by the way the room temperature goes up in steps. The 'treads' are where the boiler goes off for a short while.This could be caused by the thermostat (make and model would help), or by the boiler short cycling (same info please). Eliminating these steps, so the room temperature increased continuously, would reduce considerably the room's heat up time.

As for your question, the fact that the room reaches the desired temperature suggests that the rad is large enough.

I think the steps are just a product of the fact I have the graphing software set up to "poll" the temperature every 5 mins, hence it is showing as steps. It's just that it's taking more than 5 mins to increase the room temp by half a degree.

 

[garmcqui]

Here's a heat loss analysis I've just done on the City Plumbing website:



It's suggesting 5042 BTU/hr, or 1.48kW. I honestly have no idea what the radiator is rated at, can't see a manufacturer on it anywhere. But most 1500 x 300mm rads I've found online are around 5100 BTU.

http://www.plumbcenter.co.uk/produc...-k2-300-mm-x-1500-mm-45-sections--5179-btu-h/

 

[Agile]

It seems that my post is invisible!

 

[Aquaheat]

I think there might be something wrong with your sums.

the bucket will continue to empty outside of heating periods. at 6:30 the bucket is empty and you will need to fill it at 2 gallons per hour and your house will not even be at the required temperature by 8:30.

Try again. Bucket will be empty at 06:30 it fills at a rate of 5 gallons in 30 minutes but loses a gallon a minute so the first half hour takes 1.5 gallons. I can then leave it to empty for the rest of the time till 08:30 as there is still enough water to cover that. It's empty again at 16:00 but I have to fill it twice in a 6 hour period.

As has been mentioned before the bucket analogy doesn't work for heating!!!!

With regards to pressure loss over 14" of bucket how much does that affect the flow rate considering the available head? It's barely negligible. Again your analogy just simply does not work and has no founding in the OPs question!

@endecotp what is your solution or ideas regarding the OPs original question?

@hazetimesfive what is your solution or ideas regarding the OPs original question?

seeing as most of you guys can't even read the graph that he provided your advice and analogies have to be questioned.

If you truly believe that leaving heating on 24/7 is more energy inefficient then i lay down a challenge.

At 22:00 tonight post a photo of your gas meter reading. Leave it on for 24 hours constant with your stat set to 21C and repost another picture at 22:00 tomorrow.

Then time it for 2 hours in the morning and 6 at night to finish at 22:00 and take another picture.

Anyone willing to accept this challenge?

Jon

Yes Me!!

Count me in

Sorry have just got in from quoting a job, fancy starting at 11?

 

[bhm1712]

I think there might be something wrong with your sums.

the bucket will continue to empty outside of heating periods. at 6:30 the bucket is empty and you will need to fill it at 2 gallons per hour and your house will not even be at the required temperature by 8:30.

Try again. Bucket will be empty at 06:30 it fills at a rate of 5 gallons in 30 minutes but loses a gallon a minute so the first half hour takes 1.5 gallons. I can then leave it to empty for the rest of the time till 08:30 as there is still enough water to cover that. It's empty again at 16:00 but I have to fill it twice in a 6 hour period.

As has been mentioned before the bucket analogy doesn't work for heating!!!!

With regards to pressure loss over 14" of bucket how much does that affect the flow rate considering the available head? It's barely negligible. Again your analogy just simply does not work and has no founding in the OPs question!

@endecotp what is your solution or ideas regarding the OPs original question?

@hazetimesfive what is your solution or ideas regarding the OPs original question?

seeing as most of you guys can't even read the graph that he provided your advice and analogies have to be questioned.

If you truly believe that leaving heating on 24/7 is more energy inefficient then i lay down a challenge.

At 22:00 tonight post a photo of your gas meter reading. Leave it on for 24 hours constant with your stat set to 21C and repost another picture at 22:00 tomorrow.

Then time it for 2 hours in the morning and 6 at night to finish at 22:00 and take another picture.

Anyone willing to accept this challenge?

Jon

Yes Me!!

Count me in

Sorry have just got in from quoting a job, fancy starting at 11?

Start tonight 22:00

 

[DaveHerns]

I think I'll accept it costs more to have the heating on 24 hrs a day ( I do this ) but I'd like to think it doesn't cost cost twice as having it on for 3 hours in the morning and 9 hours in the afternoon/evening? I've got a programmable room thermostat set a few degrees lower overnight and during daylight hours
I'm not sure now but to me it's worth the extra cost when I have to get up in the night for a wee

 

[Agile]

Heat loss is proportional to the temperature difference between inside and outside.

So having an overnight setback is not so costly.

But most would setback to a more economic temperature like 14 C.

No point in heating much when you are under a good duvet.

You have still not read or replied to my previous posting.

Tony

 

[D_Hailsham]

I think the steps are just a product of the fact I have the graphing software set up to "poll" the temperature every 5 mins, hence it is showing as steps. It's just that it's taking more than 5 mins to increase the room temp by half a degree.

Are you saying that you can only measure the temperature to the nearest 0.5C?

Do you know if the boiler is cycling?

What thermostat do you have?

 

[PullerGas]

Heat loss is proportional to the temperature difference between inside and outside.

So having an overnight setback is not so costly.

But most would setback to a more economic temperature like 14 C.

No point in heating much when you are under a good duvet.

You have still not read or replied to my previous posting.

Tony

Very true Tony.
The OP is missing the main point regarding heating his room; he's heat emitter is a radiator, giving of mainly convection heat, so the warmest part of the room is the ceiling!! So if his fancy dancy load of boll.cks controls are nowhere near the radiators convection currents he's farting at thunder. With radiators & a rectangular room you'd always site two radiator diagonally at each end of the room.
Bucket & heatloss what a load of pi.h!!!

 

[PullerGas]

I think the steps are just a product of the fact I have the graphing software set up to "poll" the temperature every 5 mins, hence it is showing as steps. It's just that it's taking more than 5 mins to increase the room temp by half a degree.

Are you saying that you can only measure the temperature to the nearest 0.5C?

Do you know if the boiler is cycling?

What thermostat do you have?

DH you're talking drivel as always, heating controls, even digi ones will always have a temperature hiatus. Measuring down to .5degC is just plain daft.

 

[PullerGas]

Here's a heat loss analysis I've just done on the City Plumbing website:

View attachment 94940

It's suggesting 5042 BTU/hr, or 1.48kW. I honestly have no idea what the radiator is rated at, can't see a manufacturer on it anywhere. But most 1500 x 300mm rads I've found online are around 5100 BTU.

http://www.plumbcenter.co.uk/produc...-k2-300-mm-x-1500-mm-45-sections--5179-btu-h/

There's every chance that'll be about 30miles out!!!

 

[D_Hailsham]

heating controls, even digi ones will always have a temperature hiatus. Measuring down to .5degC is just plain daft.

You are missing the point. The OP is not sitting up each morning reading the temperature from the thermostat every five minutes. He has a Raspbery Pi, presumably with a k-type temperature sensor attached, to automatically record the temperature every five minutes. The sensor should be able to measure the temperature to an accuracy of 0.1C. Incidentally digital room stats may display temperatures in 0.5C steps, but they can measure to a greater degree of accuracy.

 

[PullerGas]

heating controls, even digi ones will always have a temperature hiatus. Measuring down to .5degC is just plain daft.

You are missing the point. The OP is not sitting up each morning reading the temperature from the thermostat every five minutes. He has a Raspbery Pi, presumably with a k-type temperature sensor attached, to automatically record the temperature every five minutes. The sensor should be able to measure the temperature to an accuracy of 0.1C. Incidentally digital room stats may display temperatures in 0.5C steps, but they can measure to a greater degree of accuracy.

A Raspberry Pi is for kids to fart around with & even with the accuracy of a K-type thermistor, it'll only measure it a certain point in the room, not give overall room temperature. So his setup is wholly inaccurate!! So you also are talking drivel!! Google doesn't have the answer to everything DH.