Heating on low all day- experiment

[User129867588]

Not sure anyone will find this useful as I know we all have different houses and boilers etc, but I trialled having my heating on all day yesterday, reduced my thermostat to 18 degrees and I spent the same on gas as previous day when the heating was on 18.5 but only on for just over an hour in morning and then for 3 hours in evening! Both days the temp on my thermostat after boiler being off all night was 14.5 degrees 🥶

House is a 2 bed semi, mid 1980’s build. Double glazing that’s over 10 years old and some getting replaced soon. House had insulation added but again that was about 15 years ago.

As seen on pictures the main expense on the gas was when heating first came on and then around tea time. I cooked on my gas hob and then all 3 of us had showers and we use a mixer shower connected to boiler for hot water. I’m with EDF on the variable rate.

I’m doing it again today and if it stays around the same I don’t see any reason for me to work in a cold house in the daytime when it costs the same (or just a tiny bit more) to heat most of the day! I can manage with 18 degrees too and still wear a jumper and extra thermals. Last years 20 degree heat is but a distant memory…….

You can usually look up the manual on line if you haven't got one.

Results are in!

Yesterday 1x 1hr and 2x 30 mins at 21, no other heating, £5.30

Today 7:30am - 8:30pm at 19, £5.61

So basically the same. It's not felt quite as warm as yesterday but it's also not felt as cold in the non heated times.

@TokyoSushi i dont quite understand. If your heating was off before going on for an hour at 21deg, how could temp reach anything like 21 deg?

In my house in the morning I could set any temp from 18.5 to 25deg and it would cost the same as it would barely reach the 18.5deg

Hive says it gets to 21, but I'm literally just completely relying on what Hive says!

Is it a pre heat option? My thermostat has that so can I set temperature to be for eg. 20 degrees between 6-7 am with preheat so basically boiler would fire up before 6 to reach 20 for the the actual scheduled time. I never use this option.

I’ve got a hive but after being off overnight would only rise to 18.5 after an hour

@TokyoSushi looks like yours might have been using the preheat option if your thermostat was already at 21 for the 1 hours time slots Hive link

My friends engineer told her to leave hers on low all the time, the thermostat will turn on and off according to the temperature of the room, its cheaper than having it on a timer and going on and heating up, according to him.

Tested this today off the back off this thread. Ordinarily we have the heating on for an hour or so in the evening and pay about £2.

Today I ran it for just shy of 12 hours, maxing out at 18. It's been lovely being warm. But at £6.30 for the day, it's not sustainable.

@RhubarbFairy it will feel like a big difference if you only put your heating on for an hour in the evening.
If I only put it on for an hour or two in the evening, the house would spend all that time getting up to temp and lose the heat very quickly, so for me it’s
more better this way but hopefully your house isnt as old as mine and better insulated 😂

We have ours set to maintain, so it heats to max 18, and it only comes on when the house is below that.

It's not that it feels like it's a big difference, it is a big difference! £2 and £6.30.
I can see that it's only cost an additional £4 for an additional 11 hours of heat which is good value compared to just one hour.

But that works out at a crazy £195 a month before we've added the electric onto it. Which as you can see, was also £6 a day. So that's £381 a month, which just isnt sustainable. This time last year it was £75 a month and we had the heating up to 22!

We're in a 1907 terrace and the insulation is shocking, so sadly it does lose heat very quickly.

I tried this yesterday so I'm now £28 poorer

Big open plan house, reasonably well insulated but there are a lot of windows. Thermostat was set to 17 all day, resisted the urge to turn it up in the evening and we were warm enough. Just can't afford to do that every day unfortunately

Eek, how on earth did it cost £28 for one day?!

@FancyFelix Oh wow! That’s a lot! Is it an older boiler that you have? It just doesn’t sound right to me! Have you got details of how many units you used and when?

That is a big difference . with my experiment it was slightly different as I was heating for about 4.5 hours. A short amount in morning and then longer in late afternoon. It’s crazy when we look back at year….

Not sure open plan homes are going to be as thermally efficient as something with more walls/rooms.

Also it depends on the efficiency/age of your boiler and the standard of your glazing/doors and the insulation in your floor, walls and roof.

...and how much hot water you use/what cooking you do.

You all need to find out what works for you...all homes are different.

My thermostat is at 17 overnight and 19 during the day. No idea how much it costs each day (no smart meter) but it's warm without being hot.

We tried yesterday, temp set at 18 degrees- 9am til 8.30. Total cost for gas and electric was £7.12.
usually a total cost of around £6.50 when we put the heating on for 3 blasts and we get very cold in between the blasts- much pleasanter experience keeping the house warm with the heating turning itself off when it gets to 18

Oh and gas oven was on for nearly 2 hours cooking a full roast as well

@FancyFelix £28, that sounds insane!

Our house is very unfashionable - the opposite of open plan, no big bi-folds or orangeries, half length curtains we tuck behind radiators. With energy costs spiralling it's staying that way. I do wonder how much more we'd be paying if we'd gone for the big double height kitchen extension with massive bi-folds.

Even without Hive, you can get a lot of fine control with TRVs and a modern, portable thermostat.

My heating engineer recommended this to me twenty years ago to leave it on all day. Back then I realised it didn’t cost me any more than turning off and then heating a cold house.

definitely worth trying imo

we have individual thermostats on each radiator with wifi based app to turn on and off, installed a five years ago so we could come home to a warm house when adhoc return timings were making life awkward. Best thing we ever did.

My curtains have been across my kitchen bifolds permanently for the past few weeks. I’m considering a blind for my roof lantern too. It’s worrying how quickly our oil levels are going down

I keep my heating on all day as I wfh and its bloody freezing in here otherwise. Draughty early 1900s house with single glazing, 3 bed but radiator is off in guest bedroom and door kept shut.

18 degrees during the day, 19.5 in evenings, 12 degrees overnight. Gas is costing about £100 a month at the moment.

I've adopted this principle since we moved here 4 years ago and got the Hive. It seems logical to me, but then I read the other month that it doesn't help and uses more gas, so thanks for the thread as I feel vindicated now!

Our place is a large apartment in an old manor house with 12 foot ceilings in most rooms - listed property so no double glazing. We had a new, highly efficient boiler fitted last year. It takes an hour to raise the temperature 1 degree. I keep the temperature at 17.5 most of the time and raise it to 19 from 5pm, so it reaches 19 from 6.30pm-ish and is set to 17.5 again from 9.30 pm. I only have the water on from 5pm to 6.30pm, so the water heats when the boiler is on for the radiators. There's only the 2 of us so that's plenty of water generally.

We have a new boiler and smart thermostat and our heating engineer recommended keeping the heating on all day. The radiators don't get hot, just warm. It's less work on the boiler to fire up at full speed every day, just gently ticking over. Whether it's cheaper, I don't know, we've only just moved into this big draughty house and replaced all the heating system so I can't really compare to previous years.