Best way to operate central heating?

[UpgradeME]

I'll definitely get some decent loft insulation up there, seems to be pretty cheap. I'm trying to find out why my first gas bill was £65/month, and the second was £175/month, despite temperatures not being all that lower; but certainly I'll do everything I can re insulation.

I paid £1 per roll from an offer nPower (delivered by local builders merchant) had for any (non npower) consumer. Looking at their site, it looks to have increased to £3 per roll but still cheap!

Without seeing your heat loss calc (earlier link) it is hard to say for certain, however, £175 to me for a 3-bed detached indicates you have a fault somewhere (gas leak, room stat, boiler or hot water leak?)

Have you noticed the boiler coming on when there is no demand for heating?

Re. keeping the house at a constant temp rather than letting it cool down all the time; what temp what you suggest is the lowest to keep it at (for rooms that aren't used much), and would you do this for all individual rooms, even bathroom etc. that is only used for maybe 1 hour a day max.? Going to get some of those individual timer valves for a number of rooms.

I have programable room stat which allows me to set different temp's at different times of the day. There is always someone at home so depending on the time of day, and day of week, my house will be between 19-20C until midnight.

2. Thanks, I'll remove them again. The lounge seems to get hotter much quicker than other rooms downstairs (with the rads on the same setting, and doors either open or half-open): is there a way to decrease the heat output of the lounge radiators (not just the TRVs) so it's more even?

Yes, you need to make sure the radiators are balanced (search on here or Google for loads of info on how to do it! (You basically alter the lockshield valves on all rads to make sure they are heating up equally and ideally with a 20C drop (or as high as possible upto 20C) between the flow and return pipes)

 

[RigidRaider]

Yes, our room 'stat is in the cooler hallway.

What I'm trying to convey is the sense that, in the end, it doesn't matter what fine adjustments you make to the heating system because it's all about the bigger picture, which is: thermal energy in vs. energy lost through the roof, considering the house as a mass of several tonnes of materials (internal walls and furniture) which will need to be in a warm atmosphere for long enough to absorb heat and then contribute to storing that heat.

This is why I think it's pointless to flog the boiler twice a day; the mass of the house and contents will never get a chance to warm up.

 

[Rich114]

Thanks Upgrade, I'll sort the insulation over the next couple of days.

I wonder if it'd be beneficial to get a competent plumber in to test everything; as it does seem very excessive, even with moderate loft insulation/inefficient settings etc. Trouble is finding one; the two I've had over so far didn't have any general or specific advice that was any help sadly.

All I've noticed is that the room temp gets up to 21° when the room thermo in the room is set at 18.5°, could be down to the lounge radiators needing balancing though? Don't think the boiler has been coming on when the room thermostat has been above the set 18.5°, though.

I guess you heat your whole house (doors open) rather than individual rooms (doors closed) then? We're trying to do the former, as there's only 2 of us here, so considering the digital TRVs for the rooms that are only used for a couple of hours a day; though I won't let them get too cold (as RigidRaider says).

Rigid: I wonder if it'd be beneficial for me to move the room thermostat to the hall (basically in between the office and lounge, that are used all day during the week), rather than in the lounge?

Understood and appreciated re. the bigger picture, I will give the loft insulation priority.

Even when we're out/during the night, the room thermo is set at 15° though, in an attempt to keep it at a low level so it doesn't take as much fuel/time to heat back up to 18.5°+ again in the morning/when we're back; but I was considering lowering the smaller rooms (bedrooms, bathrooms) to 10° or less when not in use, with the doors closed...

 

[RigidRaider]

Jeeze, Rich114, you're thinking too much, man!

Yes, the hallway is a better place for the room 'stat because it doesn't suffer the peaks and troughs of temperature of the lounge and in our case, the hallway being relatively poorly insulated it reflects the outdoors temperature more accurately.

Now go away and make yourself a nice cup of tea, then come back and start checking glass wool prices with all the local wholesalers or distributors. Somewhere you'll find a good price AND sold by someone with a big van who will deliver, saving you all that hassle!

 

[Rich114]

Jeeze, Rich114, you're thinking too much, man!

Yes, the hallway is a better place for the room 'stat because it doesn't suffer the peaks and troughs of temperature of the lounge and in our case, the hallway being relatively poorly insulated it reflects the outdoors temperature more accurately.

Now go away and make yourself a nice cup of tea, then come back and start checking glass wool prices with all the local wholesalers or distributors. Somewhere you'll find a good price AND sold by someone with a big van who will deliver, saving you all that hassle!

lol; just want to make sure all the bases are covered and I have all the facts so I can be paying for the minimum amount of gas I need

But, yes, I do tend to over-think things

 

[UpgradeME]

Now go away and make yourself a nice cup of tea, then come back and start checking glass wool prices with all the local wholesalers or distributors. Somewhere you'll find a good price AND sold by someone with a big van who will deliver, saving you all that hassle!

OP, as your a BG customer, you might want to look here http://www.britishgas.co.uk/energy-efficiency/free-insulation.html as BG are offering free loft insulation! or if you want to do it yourself, nPower's £3 per roll (delivered price) will be hard to beat!

All I've noticed is that the room temp gets up to 21° when the room thermo in the room is set at 18.5°, could be down to the lounge radiators needing balancing though? Don't think the boiler has been coming on when the room thermostat has been above the set 18.5°, though.

You might want to check the actual room temp with another thermostat (just in case your room stat is faulty!?) - I heat my whole house, appart from one spare room (which I keep the door shut, & the TRV set to frost protection) to 20C in the morning, letting it drop to 19C during the day, then increases again to 20C in the evening, then down to a set back temp of 16C during the night.

If your "over shooting" the temp, your boiler is working longer than it should be and therefore using more gas. The cause of which could be any number of things. I would start by;

1, Re-locating the room stat in the hall, at the height/location specified in it's installation instructions.

2, Perform a whole house heat loss calculation to give an indication on how much energy your should be using and post back here.

3, Arrange for or purchase and fit additional loft insulation if less than 270mm thick.

4, Check for hot water leak i.e. with the heating turned off, is the boiler still firing heating hot water?

5, Check for gas leak as per earlier replies.

6, As your a 'detail' person, you could take daily meter readings now and when making any changes, you will then see if your change makes any difference! (other conditions apply here such as outside temp and cooking/DHW usage etc but it worked with me..) As an indication, at the current outsite temps, I would typically use 1.57 units or around 50 kWh of gas per day which gives a monthly price of £62 on my BG bill (Websaver 12 tariff). Calc to convert meter units to kWh is: (((T4*100*1.02264)*0.0283)*39.4)/3.6 where T4 is the difference between daily meter readings.

Monitoring daily usage may give you an indication e.g. if you see a big jump on certain days

7, Check / balance your radiators (I brought a IR thermostat off eBay for around £10 to do mine)

8, Who serviced your boiler? Did the usage increase happen straight after the 'service'? Perhaps ask the engineer if he changed anything which could affect gas usage?

9, Don't forget to drink your tea!!

10, Report your findings from the above here for further help/support.

 

[Tinitus]

Long thread and I have not Read it all But wondering do you have any gas fires or other gas appliances that you have started using. Living flame gas fires can be very thirsty. are your cavity walls insulated, do you have any open flues or draughty rooms ie big gaps around skerting boards with timber floors. is it worth having meter changed to a smart meter you can then keep a close eye on usage.

Paul

 

[ALEC1]

its all very relative... the other day I asked the client how the gas bill was, she said too much...

then I said lets see the gas bill, and we worked out that her gas consumption was 16kwh a day for a family of three...given that a sustainable world is achievable at 12kwh a day per person, this person was living her sustainable dream and still un happy...

gas costs. It was kept artificially low for along time..we are beginning to realise that!

 

[UpgradeME]

its all very relative... the other day I asked the client how the gas bill was, she said too much...

then I said lets see the gas bill, and we worked out that her gas consumption was 16kwh a day for a family of three...given that a sustainable world is achievable at 12kwh a day per person, this person was living her sustainable dream and still un happy...

It takes me 8kWh just to heat the DHW twice per day! - I'm guessing your customer didn't use their boiler much?

A quick calc reveals that at £175 per month, the OP is using approx 139 kWh of gas PER DAY to heat a 3 bed detached. (Assuming he's on a silimar BG tariff to me)

 

[ALEC1]

its a combi with a modulating/compensation controller, its a small two up two down 20 year old end of terrace house.. they had the room temperature programmed at 20, although I did not see the hours...

even though they have a baby...I thought the house was a bit cool...

 

[Rich114]

Upgrade: good find with the BG loft insulation, they're coming out on Friday to do a survey. Also going to see if the wall cavities have been done.

I have the room stat set to 19 during the day, and back to 15 at night, so similar settings to you.

1. I've now re-located the room stat to the hall, approx 1.5m high, and will see if that works better than it being in the lounge. Lounge TRVs are now back on, set at 3, which seems quite comfortable. Though, I'm concerned I'll be using more gas as the hall radiators are set lower than e.g. the ones in the lounge and office (as the hall doesn't need to be as warm); so won't the boiler be on longer as the room stat will now take longer to get up to temp?

2. Will do, thanks.

3. Arranged!

4. When the heating is off (e.g. when room stat was fully off on Saturday), the hot water takes a very long time to come through. So I'm guessing this is okay?

5. Turned heating full off on Sat, went out for 3 hours and we hadn't used any units by the time we came back. Though, even at my crazy high usage of +2.7x, that time would only equate to 1-2 units, so I may have not seen any change during that short period anyway? May be best to do it over a longer period e.g. a day?

6. Already on with this (haha); though I've been doing it per week. I made some changes last Wed at 9pm (removed all heater cabinets, changed settings on room stat and TRVs, started shutting more doors etc.), so I'll have a look tomorrow to compare my usage with the previous week's.

7. Got a plumber out also at the end of this week, so will ask him to balance.

8. The increase happened around the time the boiler was serviced; but that also coincided with it getting into Winter, and apparently BG prices increasing, though I still doubt the slight drop in temp and increase of BG prices would equate to a usage increase of 270%! So you could be right about the boiler, I will ask him.

9. My tea was very welcomed and helped me to stop stressing as much

10. After the plumber's been and loft insulation in, I'll do the heat-loss calc and take regular readings etc., as there won't really be anything further I can do at that point I don't think...

pwdavis: No unfortunately not; the fire we has is electric (never use it); cavity walls I'm not sure, but will find out on Friday when the BG engineer comes; draughty rooms: we have a uPVC DG door separating the utility/garage from the house, so that should be okay; the only room that gets very cold is the dining room (it has an exposed stone wall as it's in the extension), which is separated from the lounge by a thin door, which seems pretty well sealed and I certainly haven't felt a draught through it, though it would be worth putting a draught excluder down.

Still, exact usage was absolutely fine (£60/month) for Sept-Nov (2 months), and we didn't change anything...

Smart meter is a good idea: is that something BG will do?

 

[UpgradeME]

1. I've now re-located the room stat to the hall, approx 1.5m high, and will see if that works better than it being in the lounge. Lounge TRVs are now back on, set at 3, which seems quite comfortable. Though, I'm concerned I'll be using more gas as the hall radiators are set lower than e.g. the ones in the lounge and office (as the hall doesn't need to be as warm); so won't the boiler be on longer as the room stat will now take longer to get up to temp?

The room with the thermostat should not have TRV's installed on the radiator(s). There should be two lockshield valves on the rad (to prevent anyone turning it off) allowing the room stat to do it's job.

4. When the heating is off (e.g. when room stat was fully off on Saturday), the hot water takes a very long time to come through. So I'm guessing this is okay?

It would depend on the plumbing but doesn't rule out a HW leak per se.

5. Turned heating full off on Sat, went out for 3 hours ... May be best to do it over a longer period e.g. a day?

Yes, needs to be for a longer period.

10. After the plumber's been and loft insulation in, I'll do the heat-loss calc and take regular readings etc., as there won't really be anything further I can do at that point I don't think...

The heat loss calc will give you a lot of insight into the issue!

Smart meter is a good idea: is that something BG will do?

Yes... at some point (see here) If you find a way of getting to the top of the queue, please let me know how as I want one!

 

[Rich114]

Thanks (again)

There are 2 small radiators in the hall, one has a TRV and one doesn't - I should remove the one that does then? This is the one that's near the lounge door, while the one without a TRV is by the porch door.

Will let you know how I get on with the SmartMeter!

 

[Bobballs]

Had simular problem in 3 bed semi, no cavity insulation as solid brick, good loft insulation and double glazed throughout. The house was a b*tch to heat up and my gas bills were large.

I was out at work all day only in during the eves and mornings, orginally just had heating come on in morn and eve and off during the day, but then I tried leaving it on all day but dropping temp to around 16.5 when I left for work. I found the on all day approach reduced my gas usage and house was alot more comftable. Someone can probably quote me numbers to say this approach doesnt work but it worked for me.

ta

 

[Rich114]

Hi guys,

Been doing some monitoring of our gas usage over the last couple of weeks.

We don't appear to have a gas leak, though I'm still waiting for the plumber to come over to have a look at the boiler etc.

In the first week (before any changes) which was about 5° avg temp I'd say, we used 95 (meter) units in the week.

I then turned the boiler down a bit, as well as the room thermostat to 19 during the day, and rolling back to 15 in the night; relocated the room thermostat to the hall, removed the radiator cabinets, and set each TRV to as low as we could stand it for each room; as well as turn off the radiator (frost setting) in another room we don't use (it's now sealed so no draught), and keeping all upstairs doors shut during the day, and most downstairs ones.

This meant the temperature was just about comfortable in each room, though not as warm as I'd ideally like, but we could get used to it if it significantly reduces the fuel we're using in the colder months.

The first week after this was 65 units, and the second week (last week when temps really went down to sub-zero), 75.

I still think this is very high though, and should be more like half of those figures?

British Gas came round to do a survey on cavity wall insulation and loft insulation: they can't do cavity wall apparently as we're stone-built; but can do the loft insulation (floor). There's a bit of insulation on the rafters in the loft, but none on the floor, so they're coming to do that apparently within 2 weeks from today.

I'll also get a couple of those digital timed TRVs I think for the bedroom and bathroom upstairs: these are relatively small rooms, so as long as I keep the doors shut all the time (as we do anyway), I'd assume there'd be a benefit to letting them go down to 10° or even off (Frost setting) apart from the small period they're needed during the day - would this be a good thing to do?

I can't imagine the loft insulation halving our gas bills though, so assuming there isn't anything seriously wrong with the boiler etc. (I'll find out in a few days when the plumber comes over), I'm stumped really as to why our usage is so high?