Is heating the home to 18oC the new 20oC?

shinytop

I think you've probably got the hang of it already. I have an Ecodan but with radiators.  You should try and get a curve that works most of the time without offsetting (the -1 to-3 adjustments).  The curve is quite configurable and you can have a point in the middle as well as the start and end values.  I do that and then use the room thermostats to limit the temperature - if it's very sunny (solar gain) or I have the wood burner going. Or like now, where it's warmer out.  It's a shame you can't time the offset with the Ecodan controller.  I just use the timer to switch the heating off 12-5am.  The house cools a few degrees and warms up slowly in the morning.  You could do a similar thing with the room thermostats.  One thing to remember is if you have a well balanced compensation curve it will take a long time to heat the house up if it gets cold.

I've done lots of experiments and measuring and the only method that makes a significant difference is running a high fixed flow and using the thermostats as a target rather than a limit.  A bit like a boiler.  That approach used about 20% more energy for the same results as I have now.  But that's my house and my ASHP; others may be different.  

If you want any more specific Ecodan info or documentation PM me.

matelodave

My Daikin does have the facility to change the offset under timer control so I knock it back by 3 degrees at 10pm and then back up at 7am.
If we turn it down too low overnight it will take a whole day to get back up to temp so it's better to run it longer at a lower temperature.

A bit like driving,a car  you get better fuel consumption at 50 than you do at 70 or 80, you still get there but it takes a bit longer

[Deleted User]

The biggest thing I now notice since December is that the CH programmer does not have free reign anymore.  It is more the case that when it comes on, it is because we are starting to feel the cold rather than turning it down/off because the house feels too hot.  Generally though the heating stat is now set at a maximum of 18C and I do pay attention to the amount of sunshine that we are going to get during the day as that can and does heat up the house faster than my CH (fortunately my bungalow has good sunshine coming to it when it is sunny!).  So this morning the lounge was only 16C at 0730 but now 1.5 hours later it is a comfortable 18.5C and rising without any CH input.  So another tweak I have done is to knock back the time that the program comes on until 0830 by which time the temperature is usually in excess of the set temperature.  And if it isn't then the CH will come on because it needs to come on.  April is starting to look very good for monthly gas kWh usage overall although it has been decent sunshine here in the NE.

So to answer the Q posed by the OP, yes 18C is the new norm (or rather the new max) for me - the CH was set higher in 2021 (at a max of about 20.5/21.0) whereas now it is set at a max of 17.5/18.0 depending on the time of the day.

fly-catchers

Went from my regular 19c to 18c this winter. And if its 17/17.5 and with jumpers feel ok don't bother putting it on.

Mstty

Update kitchen was 17.9oC this morning and SWMBO said her toes were going to fall off. Looked at the weather forecast so ordered a pair of USB heater slippers from fleabay at £10. Was going to buy these anyway for October and winter for her.

Wonder if they will work lol

I refuse to turn any heating back on. Down to an average 8kWh electricity a day which trust me is very good for our usage and lifestyle as we both work from home.

If we keep this up over summer we predict a 500 kWh (£150) saving over the next 5 months before we hit winter and set the temps down on last year's heady 21oC!! (Going to try 18oC but suspect 19oC will be the compromise)

(From.the household spreadsheet)

Predicted saving £150

USB heated slippers -£10
Electric over blanket -£37

(Personal and top of bed use)

5 months predicted savings £103

MovingForwards

I wear slipper socks or if it's approaching 0° slipper boots too. In winter it's lined slipper socks and slipper boots, still got all my toes; always useful as I like to paint them to match my finger nails.

I've not got a thermometer to say what the temperature is in my home, but the heating isn't on and my OH is in t-shirt. We haven't long closed the windows.

Only the hall and bedrooms have carpet, old property in Scotland.

Does SWMBO wrap up or does she think year round summer dresses are fine for the house. 

Perhaps there should be a new version of wife swap, where they do a week in a different property and have to adapt to lower temperatures.

Magnitio

Over the past two years I've been reducing the thermostat temperature from a typical 19 down to 17.5 during the day and 18 in the evening. My OH has gradually become used to it, though it will sometimes go up to 19 for an hour. We both grew up in houses that were much colder. Gas usage has dropped by over 20% as a result.

Mstty

@MovingForwards

I don't think my OH could.survive in Scotland but I like the idea of this kind of swap as you don't know how good you have got it.

It's definitely dawning on the household that we have to look at other ways to keep warm next to me in a full length cardigan and two pairs of socks.

Swipe

All storage heaters are off now. Just ran a 2KW fan heater for 20mins on cheap rate to warm the kitchen up. Now a toasty 22C that should keep it above 18C until the sun comes out.

MovingForwards

@Mstty I have four seasons up here, sometimes all in a day. In winter I can be outside in a summer outfit or standing in snow. I get a tan each year just because of pottering about. 

Inside I've a fleece blanket from pr1mark to slip over my lower half if I get a bit cold.

Didn't have DG / GCH before I moved up here and only had working GCH in this property and my last one, therefore it's 'normal' for me to wrap up.