How many units of Gas are you using daily?

idrilaki

KimYeovil wrote: »

Seven days some years (literally), seven weeks at most most years. Seven months is just crazy. If you're wealthy and can afford to do that, then bully for you. Seems a shocking unnecessary waste to me.

I'm the culprit in this one, littleange was questioning me.

I am not wealthy - far from it. I don't see the merits of returning to a home that's below 10 degrees and needs three hours to be warmed to a decent level where you don't need mittens and coats, though, by which time it's bedtime already. I did choose to live in a colder country than mine (I come from Greece) but I refuse to live a frozen miserable life.

If you're made of sturdier stock than me, then great for you!

espresso

Cardew wrote: »

espresso,
Is that 18kW the output or input?

I assume your house is modern and has high standards of insulation? as 18kW seems low for a 4 bed detached.(or perhaps I am out of touch)

The Combi I have is for an annex(a small detached converted Coach House) of approx 900 sq ft and that has an input of 30kW and a nominal output of 24kW, although I suppose a combi needs a higher rating to provide 'instant' hot water.

Yes our boiler is rated at approx 18kW or 60,000 Btu output. I'm not familiar with the Bermuda 551 back boiler, so yes that could be an important factor. Our property is not new but has double glazing, cavity wall/loft insulation etc.

alan260760

I too have the same system, installed 37 years ago, touch wood, working brilliantly. I am looking to replace the floor vents, any ideas where I can get some

littleange

I was just curious really, personally. I am sitting here with my fingerless gloves on, a top, jumper, dressing gown, socks up to my knees and big chunky homer slippers it's currently 14C in the house but regularly topping up my hot water bottle and popping the 450w heater on from time to time to take off the chill and also jumping in the bath every night to warm up before bed. It's not quite cold enough for my hat yet or to be tempted to put the cental heating on. However, I might just stick it on to see how much it uses and make sure I've turned off unecessary radiators. You get used to the cold (I think most people have just been spoilt by the heating) and then when you go to other people's houses you feel like your going to pass out and you can't wait to get back to your nice cool house.

Cardew

derrick/espresso

I have read several times that the output of any back boiler is no greater than 16kW; viz

Back boilers offer a space saving advantage because they fit into the opening behind a fire surround and are then hidden by a gas fire. The disadvantage of a back boiler is that the output is limited to 16kW (55000BTU/hr)

Assuming that this also applies to the Baxi Bermuda 551, it means that the efficiency is in the order of 50% if it can use 30kWh in an hour. That also ties up with other website that talk of back boilers having low efficiency.

However even at 50% and assuming espresso had the latest all seeing, all dancing, condensing boiler giving 90%, it doesn't explain why his consumption in a 4 bed detached is so much lower than a 3 bed semi. There must be other important factors.

Incidentally I share derrick and other's sentiments about keeping old boilers that soldier on for years without repair.

It costs £thousands to adapt and fit a new boiler. They have pitiful guarantees, and seemingly built-in obsolescence where 10 years is considered a reasonable life. Firms like BG with their very expensive boiler cover schemes do not cover the heat exchanger.

littleange

Just tested our water and then our heating, we have a 20 year old Glowarm or Glow worm boiler I think (it's under the house - and I'm not going in there ) 3 bed semi.

1 hour of water heating = 0.797units x 11kWh = 8.767kWh x 3.77p (Ebico) = 33.1p

1 hour of heating 6 out of 10 radiators on 3/4 = 1.726units x 11kWh = 18.986kWh = 71.6p

Last time I tested way back I'm sure it was 30p for the heating and I thought that was a lot back then!

Our little 450watt heater in our room only uses between 4-7p an hour, so think we will stick to just keeping one room warm for now. That is between 10-18 hours of heater for the same price as 1 hour of central heating!

Mazio_2

Cardew wrote: »

These figures on how many kWh used per day are fairly meaningless unless the size of the property, insulation standards, temperature maintained and type of occupation(all day or out at work) are taken into account.

I suspect it uses more gas to keep Buckingham Palace at 24C than a bedsit at 16C!!

This should also include how many live in the property as I have 4 children (although only 2 live with me all the time) this has a major bearing on usage and how many rooms I keep warm.

At present I am using 65-78 Kwh/day GC heating (this is a big reduction if we keep it up on last year average 128Kwh/day) on for 1 hour in the morning and and 6 hours evening, This maintains the majority of my house at 19-21c ( 2 rooms at present rads switched off) I have though increased electric consumption slightly (average at present 15units per day) as I use an electric immersion which for me works out slightly cheaper to run.
If I keep this on all day I will use a minimum of 15 possibly 30 Kwh more per day. So for me its cheaper to only have heating on when we are at home.

Cardew

Mazio wrote: »

I use an electric immersion which for me works out slightly cheaper to run.

How is an immersion cheaper to run?

If you are on Economy 7 it might be, but what about the extra you pay for daytime electricity.

With the huge increases in price for night rate electricity, the 'break even' point for E7 has risen dramatically. On BG click 6 it is over 50% - very difficult to achieve with gas CH.

ezrollers

littleange_com wrote: »

I was just curious really, personally. I am sitting here with my fingerless gloves on, a top, jumper, dressing gown, socks up to my knees and big chunky homer slippers it's currently 14C in the house but regularly topping up my hot water bottle and popping the 450w heater on from time to time to take off the chill and also jumping in the bath every night to warm up before bed. It's not quite cold enough for my hat yet or to be tempted to put the cental heating on. However, I might just stick it on to see how much it uses and make sure I've turned off unecessary radiators. You get used to the cold (I think most people have just been spoilt by the heating) and then when you go to other people's houses you feel like your going to pass out and you can't wait to get back to your nice cool house.

Thanks m8, I've just read your post aloud to my gf and she was glad that I keep the house between 17-18 C and not 14 C. I'm sure she'll resume moaning in a few days, but for the time being you have just bought me some peace and quiet

Incidentally, Electricity use is around 3-4 kWh per day. Gas rather depends on the weather. Last week it was about 20 kWh per day, week before that 32 kWh per day :eek:

Mazio_2

Cardew wrote: »

How is an immersion cheaper to run?

If you are on Economy 7 it might be, but what about the extra you pay for daytime electricity.

With the huge increases in price for night rate electricity, the 'break even' point for E7 has risen dramatically. On BG click 6 it is over 50% - very difficult to achieve with gas CH.

The problem for me is I did an large extension 15 odd years ago and moved my boiler to the other end of it probably 30 odd feet further the system is gravity feed with 22mm pipes flow and return 60 foot running in an lean too roof of my extention (so any heat loss by the pipe insulation is lost) this then is indirect heat in the hot water tank so iam heating allot of pipes to get to my tank I also cannot at present control the hot water temp from my gch .
This year I had the tank decreased with factory fitted insulation and fitted an electric immersion 117L tank this heats up rapidly within 15-30 mins already plenty of water for bath / shower. I was using nearly 1 unit of gas 31 Kwh in the summer per day to heat up my water I believe most of this is the pipe run length. regardless of how many showers/baths and the electric immersion is dependant on how much hot water we use but my calcs tell me its cheaper only by a few pence say 10-20/day and i switched the boiler off for the whole summer at present both systems heat my tank obviously the electric immersion at present only comes on if the gch is off or we use allot of hot water quickly.
By the way I dont have E7 because I would need a very large hot water tank and would have needed to heat it up through the night with some days 2 -3 showers in the morning alone which would probably leave me with no hot water for the daytime let alone evening.
I do agree though for most people it should be alot cheaper with gas. But remember the efficiency in older boiler systems is say 60% of that with heat loss and controls perhaps not at optimum you could be down below 50% using gas and electric is 100% efficient and gas prices rising more then electric in recent years also a good insulated hot water tank losses very little heat.