Putting Heat on for every second hour?

PatrickSmithUS

Is this efficient?


I always presumed that this is a smarter and cheaper way to keep the house warm that just having it on all evening.

GarIT

Is no more or less efficient. Assuming you keep the temperature of the rooms the same.

PatrickSmithUS

GarIT wrote: »

Is no more or less efficient. Assuming you keep the temperature of the rooms the same.

Would it be less heavy on the oil if it's only burning half as much?

weemcd

PatrickSmithUS wrote: »

Is this efficient?


I always presumed that this is a smarter and cheaper way to keep the house warm that just having it on all evening.

That's kind of what I'm doing atm. My place is kinda drafty and doesn't keep the heat well. I'm working from home though and I don't want to have it on all day. At the moment I'm hitting it on for an hour then leaving it a while until I feel the need to stick it on for an hour. I've found this year to be fairly mild so far, so I haven't had to have it on for too long yet and get stung with a massive bill in January.

Interested to see other opinions for who knows what they're talking about

GarIT

PatrickSmithUS wrote: »

Would it be less heavy on the oil if it's only burning half as much?

No it burns the same amount.

To achieve any particular termerature a fixed amount of heat energy is required (depending on things like the starting temp and temp of the room) and that will require burning a fixed amount of oil if you are using the same boiler in both cases.

Your boiler will use much less oil to keep radiators warm than it will to heat them from cold. Over the course of the two hours the amount of oil used would be the same. Once again that is assuming the same temperature is kept in the room in both scenarios, if in one scenario the room is allowed get warmer or colder than the other that will use more or less fuel.

Car99

Depends on how well your house retains heat.

GarIT

Car99 wrote: »

Depends on how well your house retains heat.

Not in this case. If you house doesn't retain heat well you will use more heat in both scenarios, but it won't make a difference between the scenarios.

B-D-P--

So what your doing is heating the radiators to cool them, How long does the rads take to heat?

Its not exactly like for like, but If I have to go from Mayo - Dublin, Would I get better fuel economy from Revving to 7k Revs & letting off the accelerator till stall & start again, or keep a steady throttle?

2nd option, Keep the heat steady.
Now if your rads are still warm after 1 hour, then it will work in your benefit. If they are cold to touch after 1 hour then your are throwing money down the oil tank.

Remember it takes more effort to get the initial degrees into water than the higher, Eg more to get from 10 - 14 than 14-18.

colm_mcm

Does having the boiler set at a lower temp for a long period work better than having at a higher temp and set to power on and off via timer?

does the pump running help in terms of heat circulation between the pipes and radiators?

GarIT

B-D-P-- wrote: »

So what your doing is heating the radiators to cool them, How long does the rads take to heat?

Its not exactly like for like, but If I have to go from Mayo - Dublin, Would I get better fuel economy from Revving to 7k Revs & letting off the accelerator till stall & start again, or keep a steady throttle?

2nd option, Keep the heat steady.
Now if your rads are still warm after 1 hour, then it will work in your benefit. If they are cold to touch after 1 hour then your are throwing money down the oil tank.

Remember it takes more effort to get the initial degrees into water than the higher, Eg more to get from 10 - 14 than 14-18.

The difference there is fuel burned to torque (kenetic energy) isn't a 1:1 linear relationship. Where fuel burned to heat is.

GarIT

colm_mcm wrote: »

Does having the boiler set at a lower temp for a long period work better than having at a higher temp and set to power on and off via timer?

does the pump running help in terms of heat circulation between the pipes and radiators?

Traditional boilers are most efficient set to around 75C. On a condensing boiler the water returning to the boiler after a lap of your house should be below 55C for maximum efficiency; Veissmann say a temperature of 68C or below should lead to the return being lower than 55C but some boilers indicate their own numbers for that. If you hot tank isn't heated to at least 60C or higher that can cause serious illness or death.

Your heating on/off should be controlled by a thermostat rather than modulated by a timer.

Yes the pump will circulate the hot water.

Brian?

GarIT wrote: »

Most boilers are most efficient set to around 75 degrees Celsius. Your heating on/off should be controlled by a thermostat rather than modulated by a timer.

Yes the pump will circulate the hot water.

This.

Set your thermostat to whatever temperature you want and leave the heating "on". 21 degrees is perfect. Life's too short to have a cold house

Wearb

Just for others reading this in the future. 75C isn't the most efficient temperature for modern boilers to be set at. Condensing boilers run much more efficiently at lower temperatures.

jimf

i think this question is a bit like asking why does a dog eat grass

there will so many answers that are correct for a particular person/ household

Car99

GarIT wrote: »

.If you hot tank isn't heated to at least 60C or higher that can cause serious illness or death.

GarlT what hot tank and death , can you explain further ?

crossmolinalad

Car99 wrote: »

GarlT what hot tank and death , can you explain further ?

water temp lower than 60 c then you will get possibly legionella in the water

Car99

crossmolinalad wrote: »

water temp lower than 60 c then you will get possibly legionella in the water

Thanks.

seamus

Brian? wrote: »

This.

Set your thermostat to whatever temperature you want and leave the heating "on". 21 degrees is perfect. Life's too short to have a cold house

If you have children under a year old, this is too high, 18 degrees is the correct temp

With so many more people working from home, there will be a mindset shift needed though. The only reason your heating should ever be "off" is to not waste money heating up an empty house if everyone is out at work/school for 6 hours a day.

serox_21

18 degrees is freezing temp.

Set you thermostat to 20-21 and leave the heating on.

If temperature drops bellow set temperature(usually 0.5 degrees) boiler will fire up for a few minutes to raise it up.

When you heat only between certain hours and keep the heat off you rooms and walls will get colder and take longer to warm up again to keep same comfort.
Starting with a cold house(cold walls) after an hour having heating on will fell warm but when heating stops it will cool down pretty fast.

Use the thermal mass of the building in order to keep a comfortable temperature by keeping heating on all the time and just top up what is lost.

My settings:

heating always on controlled by thermostats:

upstairs:
20 degree during day
21 degree during night

downstairs
20 degree during day
19 degree during night(10:30PM - 5:30 AM)

GarIT

serox_21 wrote: »

18 degrees is freezing temp.

Set you thermostat to 20-21 and leave the heating on.

If temperature drops bellow set temperature(usually 0.5 degrees) boiler will fire up for a few minutes to raise it up.

When you heat only between certain hours and keep the heat off you rooms and walls will get colder and take longer to warm up again to keep same comfort.
Starting with a cold house(cold walls) after an hour having heating on will fell warm but when heating stops it will cool down pretty fast.

Use the thermal mass of the building in order to keep a comfortable temperature by keeping heating on all the time and just top up what is lost.

My settings:

heating always on controlled by thermostats:

upstairs:
20 degree during day
21 degree during night

downstairs
20 degree during day
19 degree during night(10:30PM - 5:30 AM)

I go much lower. Upstairs is 16 during the day, 14 during the night, and 21 in the morning and bedtime. Downstairs is 21 from morning till bedtime and 10 during the night.

serox_21

Actually heating the house depends on the comfort of people living in it.

Less that 19 degree fells freezing temperatures for me and my family.