Daily gas usage query

[***sausage***]

Just wondering what is the daily average for gas usage on a typical 4 bedroom house.
We’ve just had our gas bill through and the cost is a lot more than normal and nothing has changed since last winter. The worst bill we ever had after 5 years in this house over winter was £130 per quarter. The central heating comes on at 5am and stays on till 10 pm and the hall stat is set at 19-20*c. The gas usage in our house is mainly for the CH and hot water. The hot water comes on twice a day for 2 hours in the morning and in the evening. We don’t really use the gas hob to do any cooking as well. The system is serviced every year as well and the house is 5 years old. The boiler is a glow-worm ultimate 50FF.
Anyway we spoke to British Gas and they’ve asked us to take meter readings every day for 7 days which we have done. The meter readings show that we are using 10 units (28.3 cubic metres) per day at 20*c on the hall stat and 7-8 units (19.81-22.63 cubic metres) per day at 17*c on the hall stat. Is this too much usage.
Our parents usage is 4 units per day and their house is a direct copy of ours but has slightly larger rooms. They have their heating on all day set to 24*c at day and 21*c over night with the gas fire on sometimes and also lots of cooking. It doesn’t seem to add up. We took meter readings in the summer and all we used was the hot water part of the system set on twice a day and that used 1 unit (2.83 cubic meters) per day.
Can anyone say is this way too much usage before we get back to British Gas.

Any help or advice would be great.

 

[EliteHeat]

There is no point in getting on to BG until you know just how much heat you are trying to replace via the boiler/rads.

£130 for a winter quarter does not seem outrageous to me.

 

[***sausage***]

Yes that was fineat £130 but the last bill was £240 from oct 2005 to jan 2006. all the settings on the rads and timer are the same from last year.

 

[scatmanjohn]

***sausage*** wrote:

and nothing has changed since last winter

except the price of gas going up by approx 50% and set to rise again.

 

[chrishutt]

The central heating comes on at 5am and stays on till 10 pm ..... The meter readings show that we are using 10 units (28.3 cubic metres) per day

The units you're referring to are each 1000 cubic feet. Each cubic foot of gas has the energy value of 1040 btu (British thermal Units) so, deducting the 1 unit you use for hot water, you are using 9 x 1000 x 1040 btus to heat the house for 17 hours each day, which works out at an average of 55,000 btu per hour, which is equivalent to having your boiler (heat input about 63,000 btu) running flat out almost the whole time.

This sounds excessive for a 5 year old house which must surely have a good standard of insulation. The figure you quote for your parents house sounds more realistic. Really you need to know what the heat loss for your house is. The builders should know the figure.

The above calculation was corrected 8.00 am Thurs following MM's post below.

 

[meldrew's_mate]

To recap, you have the heating on for 17 hours each day, and typically use 10 units of gas (1000 cu ft). Each cu ft contains about 1040 btu/hr, so over 17 hrs you have used about 1 million btu/hr, or 61000 btu/hr for each hour of the 17. As Chrishutt said, this equates to your boiler running almost continuously during those 17 hours, so you have
1. The wife at the front door chatting with the door open for 17 hours, or
2. A faulty gas meter, or
3. A way of dispersing all that heat, eg a leak of heating water under the floor, or
4. Other fault.

You can do nothing about 1, it's genetic; to check and eliminate 2 spend an hour watching and timing the boiler, record its burner ON time and OFF time. If the ratio of ON to OFF is >90% your meter is probably OK and you need to look for ways that the heat is being used/wasted.

Try timing the gas consumption when the burner is ON over a one minute period (each full rev is 1 cu ft, each unit is 100 cu ft.) You should measure about 1 cu ft / minute. Is this so?

Take a look in the loft, does it resemble a sauna?

Finally, get a CORGI fitter to check the gas pressure at the meter and at the inlet to the boiler, if it's low at the meter (and meters are volumetric devices) you'll be getting less gas than you're paying for and your boiler will put out less heat, leading to the symptoms you describe.

An interesting post, keep us informed please.

 

[ChrisR]

See if your meter's regulator (thing on the input side) has a small black cap with Donkin written on it. If so they do go wrong a lot. If you query the pressure Transco will probably replace it, but you may need a corgi on board.



Recently found an area where the street pressure goes down to 14mb in peak times. Called Ofgem to ask what their policy is on making gas suppliers keep the pressure up. Only succeded in getting an ignorant obdurate woman telling me to report it to Transco. I already had of course. Next time in the area at 6pm I'll measure it again.

The Transco man was thick as a plank as well. 43 years time served so you couldn't tell him anything. Reckoned there's just as much gas in a cu ft at 14mbar as there is at 21. Asked him why the meter's whizzing round then, and he left saying he wasn't going to argue.

Compared with dorks like these, Corgi almost seem intelligent.

 

[***sausage***]

Thanks for the replies guys,
The insulation is as it should bein the loft and its freezing up there at the moment. As mentioned before this is the first winter that our gas cost has risen massively. whether its down to usage or gas prices we dont know yet. I'll check the meter later to see what regulator it has on it and maybe get the gas engineer back again to check the pressure. Last night i renewed the hall stat with a new one and set it to the same 20*c. i will take a reading later as well to see if the usage is any less that 10 units with this one.

 

[***sausage***]

one thing i did notice is that when the boiler is on and using gas, the 3 red digits on the meter are whizzing round. roughly per 10 secs the far right red digit goes round 1.5 turns (15 red units) if that makes sense. i will check accurately later anyway and report back with the findings. we spoke to our gas engineer and he said that he couldn't really check anything and advised us to ring BG to get the meter checked. As mentioned before our house is only 5 years old and mostly up to date with the insulation regs. we also dont have the gas fire on anymore and are not in most of the day as we both work.

 

[***sausage***]

Right,
the gas regulator is a Jeavsons J42 PRS3 and has a black cap on top of it which has a tamper seal attached.
I measured the red unit usage (to the right of the main black ones) when the boiler is on and burning and its 37 red units per 60 secs. Since changing the hall stat radiators dont seem to be as hot as with the old hall stat but the house temp seems to be the same. If fact we've turned it up to 22*c as its a bit cold outside at the moment. The days usage from yesterday seems to have gone down a bit (from 10 units to 8 units) with a higher hall stat setting. Maybe it turned out to be the hall stat, i dont know. I'll continue to monitor the usage per day to see if the trend has fallen.

 

[scatmanjohn]

Imagine my suprise when i got my gas bill today.
18% lower than the same period last year.

Got myself better loft insulation,draft excluders galore & new triple/double glazing
But best of all a programmable room stat that the missus doesn't understand