Gas on constantly or on and off...?

HappyMJ

Biggles wrote: »

That's the only thing that's certain. It's not only endless, but it starts up again at this time every year, with people comparing their (totally different) houses with other people's and insisting their usage and experience proves that they are right (whatever it is they are trying to prove!).

Completely pointless.

Quite fun though. 5 hours with the boiler not firing I love that one. My heater's been firing about every 5 minutes and stays on for about 5 minutes for the last 5 hours. If I had turned it off 5 hours ago my house would now be cold.

inaminute23

There is no apperently about it. Everyone's homes are different. Mine has just one external wall, some have 2. My lounge will now drop considerably now as.I'm doing the timer test. I will post the lounge temp in the morning

Swipe

inaminute23 wrote: »

Jut over 4 hours since my boiler last fired, and my heating has now dropped 1 degree.

You need to do this test when the weather is consistent as half way through your test the temp is about to rise considerably.

inaminute23

Ok, on timer over night. came on at 6am for 1 hour. Stat got upto 18 deg, and boiler used 0.5 units of gas. alot lower than on constant, but didn't get to desired temp. However it will be tonight when it matters nearly 12 hours of no heating.

JasX

inaminute23 wrote: »

Hot water freezes quicker than cold because the sudden shock in temp

No, we can see why you are struggling with basic thermodynamics
here

inaminute23 wrote: »

but my living room is inside my house not outside,

That doesn't except it from the same laws of physics as the cups, its a bit better insulated, and has a means of being heated. but no magic pixie dust

inaminute23 wrote: »

how silly! Plus i don't lose much heat because it tops up during the day.

No you are constantly losing heat, the fact you keep yourself at 20 DegC rather than 10 DegC means you lose heat to the outside environment at a faster rate, unless you've found a way to create or destroy energy other than the gas you're paying for you're leaking out at a hell of a faster rate when you 'top up'

inaminute23 wrote: »

The fact is since i got in at 6.45pm with my heating on all day the desired temp (19) has not dropped at all, and the boiler was last burning gas at 7pm!!!

Oh dear expalin that?

check your meter, it's been burning during the day, probably just before you wandered in the door. Fundamentally you don't get to create or destroy energy, you just get what you pay for and lose it to the outside world at a rate proportional to the temperature your house is at at any given point in time :A

JasX

inaminute23 wrote: »

Ok, on timer over night. came on at 6am for 1 hour. Stat got upto 18 deg, and boiler used 1.4 units of gas. Lower than on constant, but didn't get to desired temp.

yes but we're evaluating cost..... not performance

we can start talking about things like system characteristic times, control loop tuning , actuator saturation, overshoot and different control 'cost' weightings if you like

inaminute23

Quote:
Originally Posted by inaminute23
Hot water freezes quicker than cold because the sudden shock in temp


No, we can see why you are struggling with basic thermodynamics
here



http://www.xs4all.nl/~johanw/PhysFAQ/General/hot_water.html

Yes it does!

inaminute23

Quote:
Originally Posted by inaminute23
but my living room is inside my house not outside,

That doesn't except it from the same laws of physics as the cups, its a bit better insulated, and has a means of being heated. but no magic pixie dust

Which loses heat quicker, a room surrounded by 4 internal walls, or a room surrounded by 4 walls, but one is external. All of the same structure, size, & same size heating?

inaminute23

Why can't people just admit that is plausible in certain homes to run there heating constant, and it be cheaper than timed? Or are all the people who say it is on here, including myself liars? Have i ever stated that it is cheaper to run your house on constant? No!

JasX

inaminute23 wrote: »

Hot water freezes quicker than cold because the sudden shock in temp

JasX wrote: »

No, we can see why you are struggling with basic thermodynamics
here

inaminute23 wrote: »

http://www.xs4all.nl/~johanw/PhysFAQ/General/hot_water.html

Yes it does!

From your own source

inaminute23's_own_link_above wrote:

While you will often hear confident claims that X is the cause of the Mpemba effect, such claims are usually based on guesswork, or on looking at the evidence in only a few papers and ignoring the rest.

Residue from hot water 'may' on rare occasion freeze before a similar uniform starting body at a cooler temperature if you juggle the balance of evapouration rate, gas content, container shape, heat loss process and what convection currents are allowed to form appropriately.

There is no 'shock' effect, and there are alot of of people happy to extrapolate/guess/make largely ignorant claims based on this rare phenomenom.

and please learn how the quote command works