Hi,

I have had ongoing problems with my gas usage. I thought my old system was
inefficient so I had a new Worcester Bosch 28i combi boiler fitted several
weeks ago, however it seems that I am still gobbling gas like it's going out
of fashion.

I had BG out to reset my meter as I am on a prepay meter and it was on the
wrong settings, but it still is eating gas. I put £10 credit in yesterday
and it has already used £5, so at this rate I am spending £150 a month which
is nuts.

I know that there are lots of factors such as insulation etc etc but I only
have a two bedroom semi and it has double glazing and loft insulation.

Firstly I need to know if I am getting ripped off by BG i.e. is my meter
metering the gas correctly (BG cannot help me on this so far as they have no
records of my payments!)

So as a starting point can someone work out for me if firstly it is even
possible for a 28i to burn that amount of gas in a 24 hour period? It's not
like it is even on full! The boiler clicks on and off so it certainly is not
burning all the time, but if it were burning all the time at full blast,
what would the consumption of a 28i be in a day? And what would that cost?

I know it can be worked out but I wouldn't know where to start :-)

Any help gratefully received,

Jason

On Wed, 01 Mar 2006 15:38:27 GMT, "Jay"
wrote:

Hi,

I have had ongoing problems with my gas usage. I thought my old system was
inefficient so I had a new Worcester Bosch 28i combi boiler fitted several
weeks ago, however it seems that I am still gobbling gas like it's going out
of fashion.

I had BG out to reset my meter as I am on a prepay meter and it was on the
wrong settings, but it still is eating gas. I put £10 credit in yesterday
and it has already used £5, so at this rate I am spending £150 a month which
is nuts.

I know that there are lots of factors such as insulation etc etc but I only
have a two bedroom semi and it has double glazing and loft insulation.

Firstly I need to know if I am getting ripped off by BG i.e. is my meter
metering the gas correctly (BG cannot help me on this so far as they have no
records of my payments!)

So as a starting point can someone work out for me if firstly it is even
possible for a 28i to burn that amount of gas in a 24 hour period? It's not
like it is even on full! The boiler clicks on and off so it certainly is not
burning all the time, but if it were burning all the time at full blast,
what would the consumption of a 28i be in a day? And what would that cost?

I know it can be worked out but I wouldn't know where to start :-)

Any help gratefully received,

Jason


The startting point is to read the meter at the start and end of 24hrs
and provide the figures. That way it is possible to calculate
whether the meter is giving impossible figures.

Secondly, which model are you talking about? Is it the condensing
Greenstar 28i or the conventional Junior or??

Thirdly, measure what the gas consumption is later tonight when it
gets colder by reading the meter at hourly intervals without the hot
water being used. This will give you a rough idea of gas use for CH
if you multiply by the number of hours that the CH is on. You can
then subtract that from the day's total to get an idea of what is used
for CH.

If you look on the web site of your gas supplier, you should be able
to find a figure to convert cubic metres of gas used to kWh and then
relate that to the cost. have a look at their tariffs and you should
be able to work out what is happening.

Also from the kWh figures you can work out whether it is likely to be
correct for the boiler. Go to the Worcester Bosch site and installer
section. Find the boiler and then the intallation manual. It will
give you the maximum input rate for the boiler in kWh and cu.m/hr of
gas.


--

..andy

In an earlier contribution to this discussion,
Jay wrote:

Hi,

I have had ongoing problems with my gas usage. I thought my old
system was inefficient so I had a new Worcester Bosch 28i combi
boiler fitted several weeks ago, however it seems that I am still
gobbling gas like it's going out of fashion.

I had BG out to reset my meter as I am on a prepay meter and it was
on the wrong settings, but it still is eating gas. I put £10 credit
in yesterday and it has already used £5, so at this rate I am
spending £150 a month which is nuts.

I know that there are lots of factors such as insulation etc etc but
I only have a two bedroom semi and it has double glazing and loft
insulation.
Firstly I need to know if I am getting ripped off by BG i.e. is my
meter metering the gas correctly (BG cannot help me on this so far as
they have no records of my payments!)

So as a starting point can someone work out for me if firstly it is
even possible for a 28i to burn that amount of gas in a 24 hour
period? It's not like it is even on full! The boiler clicks on and
off so it certainly is not burning all the time, but if it were
burning all the time at full blast, what would the consumption of a
28i be in a day? And what would that cost?
I know it can be worked out but I wouldn't know where to start :-)

Any help gratefully received,

Jason

It would help if you told us what tariff you are on. How much do you pay for
a kilowatt-hour of energy. Without that information, no-one has a clue how
much gas your £5 will buy.

On the assumption that the 28i is a 28 kilowatt boiler, if it ran full chat,
continuously, it would use 28 x 24 = 672 kilowatt hours in a day. [That
assumes that the 28 kW is the *input* power. If it's the output, the input
will be upwards of 10% higher when efficiency is taken into account].

I currently pay Scottish Power 1.326p per kW-hr for gas plus a standing
charge of about 15.5p per day - so 672 kW-Hrs would cost me just over £9,
including standing charge. But my prices are capped for 3 years - so BG will
be a lot dearer than that - particularly when using a pre-payment meter.

Having said that, I wouldn't expect a 28kW boiler to have a duty cycle of
more than 25% to heat a 2 bedroom semi - unless you leave all the doors and
windows open!

FWIW, I have a 4-bedroom detached house, and we have a 96-year-old living
with us - so the heating is on every day from early morning 'til late
evening - plus a gas fire for a lot of the time. I have used 5624 kW-Hrs of
gas for the whole of February - which works out at just about 80 quid,
including standing charge.
--
Cheers,
Roger
______
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spam.

"Andy Hall" wrote in message
...
On Wed, 01 Mar 2006 15:38:27 GMT, "Jay"
wrote:

Hi,

I have had ongoing problems with my gas usage. I thought my old system
was
inefficient so I had a new Worcester Bosch 28i combi boiler fitted
several
weeks ago, however it seems that I am still gobbling gas like it's going
out
of fashion.

I had BG out to reset my meter as I am on a prepay meter and it was on
the
wrong settings, but it still is eating gas. I put £10 credit in yesterday
and it has already used £5, so at this rate I am spending £150 a month
which
is nuts.

Is your meter using ft^3 of gas and calculating it as a m^3?

Marcus

In an earlier contribution to this discussion,
Marcus Fox wrote:


Is your meter using ft^3 of gas and calculating it as a m^3?

Marcus

It would actually be worse the other way round - because imperial meters
work in *hundreds* of ft^3 - and 100 ft^3 is in the region of 3 m^3.
--
Cheers,
Roger
______
Please reply to newsgroup.
Reply address IS valid, but is disposable in the event of excessive
spam.

Further info:

My supposed tariff is 4.633p per Kwh for the first 1143 kwh per quarter and
then 2.617p per kwh for the rest.

In an earlier contribution to this discussion,
Jay wrote:

Further info:

My supposed tariff is 4.633p per Kwh for the first 1143 kwh per
quarter and then 2.617p per kwh for the rest.

OK, a lot depends on how the meter actually implements this dual-rate
tariff. [My experience of pre-payment meters is limited to the
shilling-in-the-slot jobby which my parents had about 50 years ago!]. IF the
meter charges you at the dear rate for all of the first 1143 kWHrs each
quarter before letting you have any cheap ones, you could still be on the
dear ones - which might explain the high rate of money consumption. In this
case, you'll only be getting about 108 kWHrs for each £5 until you reach
1143.

If, on the other hand, it does it on a daily basis, it should charge you
4.633 for the first 12.7 (or thereabouts) kWHrs per day, and 2.617 for the
rest. In this case, you would get about 181 kWHrs for £5. For a 28kW (input)
boiler, this would represent a duty cycle of about 27% averaged over a 24
hour period - which is at least *possible*.

As Andy H has suggested, you need to keep reading the meter frequently, and
calculating the actual consumption, in order to see whether the meter is
charging you correctly or not.
--
Cheers,
Roger
______
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"Roger Mills (aka Set Square)" wrote in message
...
In an earlier contribution to this discussion,
Marcus Fox wrote:


Is your meter using ft^3 of gas and calculating it as a m^3?

Marcus

It would actually be worse the other way round - because imperial meters
work in *hundreds* of ft^3 - and 100 ft^3 is in the region of 3 m^3.

Yeah, got up much earlier than I was accustomed to and tired after a long
day.

Marcus

On Wed, 01 Mar 2006 15:38:27 GMT, "Jay"
wrote:

Hi,

I have had ongoing problems with my gas usage. I thought my old system was
inefficient so I had a new Worcester Bosch 28i combi boiler fitted several
weeks ago, however it seems that I am still gobbling gas like it's going out
of fashion.

I had BG out to reset my meter as I am on a prepay meter and it was on the
wrong settings, but it still is eating gas. I put £10 credit in yesterday
and it has already used £5, so at this rate I am spending £150 a month which
is nuts.

I know that there are lots of factors such as insulation etc etc but I only
have a two bedroom semi and it has double glazing and loft insulation.

Firstly I need to know if I am getting ripped off by BG i.e. is my meter
metering the gas correctly (BG cannot help me on this so far as they have no
records of my payments!)

So as a starting point can someone work out for me if firstly it is even
possible for a 28i to burn that amount of gas in a 24 hour period? It's not
like it is even on full! The boiler clicks on and off so it certainly is not
burning all the time, but if it were burning all the time at full blast,
what would the consumption of a 28i be in a day? And what would that cost?

I know it can be worked out but I wouldn't know where to start :-)

Any help gratefully received,

Well, we are in a 3 bedroom mid terrace, 30+ year old boiler, paying
by direct debit, adequate levels of insulation but a draughty front
door and we pay on average around £25 per month.

£150 *is* nuts.

sponix

Roger Mills (aka Set Square) wrote:
In an earlier contribution to this discussion,
Jay wrote:


Further info:

My supposed tariff is 4.633p per Kwh for the first 1143 kwh per
quarter and then 2.617p per kwh for the rest.


OK, a lot depends on how the meter actually implements this dual-rate
tariff. [My experience of pre-payment meters is limited to the
shilling-in-the-slot jobby which my parents had about 50 years ago!]. IF the
meter charges you at the dear rate for all of the first 1143 kWHrs each
quarter before letting you have any cheap ones, you could still be on the
dear ones - which might explain the high rate of money consumption. In this
case, you'll only be getting about 108 kWHrs for each £5 until you reach
1143.

If, on the other hand, it does it on a daily basis, it should charge you
4.633 for the first 12.7 (or thereabouts) kWHrs per day, and 2.617 for the
rest. In this case, you would get about 181 kWHrs for £5. For a 28kW (input)
boiler, this would represent a duty cycle of about 27% averaged over a 24
hour period - which is at least *possible*.181

27% of 28kW @ 90% efficiency is 6.8kW of output, which is a *hell* of a
lot for a 2 bed flat.

This is a 2 bed flat, right? If it's a big 2 bed flat with say 1.5kW in
the living room, 1.5 kitchen/dining, 1kW each bed, 500W hall, 1kW
bathroom, then that comes to 5500W.

So make the rads slightly bigger and they still have to be on *all* the
time.

I don't see how on those figures the meter can be correct.

Ben

Right, I've done some further calcs, which seem to suggest that the meter is
not at fault...

I checked my meter reading (credit in pence left,) and waited for it to
clock down, it jumped down by 3pence (standard increment) so I noted the
cubic metre reading, which was 3602.796, I strated my stopwatch and turned
the hot water tap on full and ran it until the credit jumped down another
3pence, it went down at 3602.897, this was 120 seconds later.

So, can you check I have done this correct please -

Gas consumed 0.101 cubic metre
convert to kwh 0.101 x 11.06 = 1.112 kwh
convert to per hour - 1.112 x 30 (because it took 2 minutes) = 33.36 kwh

The output of my boiler on the hot water is supposed to be 28kwh, so an
input of 33.36 kwh might be about right?

Have I worked this out correctly?

If I HAVE worked it out correctly I what else could I look at next - just
checked the metre and I only have used £4.20 in gas since 3:30pm yesterday.
We have not used any hot water (apart from a couple of hand wash basins
full) and the heating has been set to 16degrees overnight. I am wondering if
there might be a problem with the gas fire which is in the lounge?

On Thu, 02 Mar 2006 13:28:35 GMT, "Jay"
wrote:

Right, I've done some further calcs, which seem to suggest that the meter is
not at fault...

I checked my meter reading (credit in pence left,) and waited for it to
clock down, it jumped down by 3pence (standard increment) so I noted the
cubic metre reading, which was 3602.796, I strated my stopwatch and turned
the hot water tap on full and ran it until the credit jumped down another
3pence, it went down at 3602.897, this was 120 seconds later.

So, can you check I have done this correct please -

Gas consumed 0.101 cubic metre
convert to kwh 0.101 x 11.06 = 1.112 kwh
convert to per hour - 1.112 x 30 (because it took 2 minutes) = 33.36 kwh

The output of my boiler on the hot water is supposed to be 28kwh, so an
input of 33.36 kwh might be about right?

It's in the ballpark, and considering you only measured for two
minutes, is reasonable.

You didn't say whether you had the 28i Junior non-condensing or the
Greenstar condensing boiler.

The specification of the Junior for an output of 27.5kW is an input of
30kW and a gas rate of 3.17 cu.m/hr. You were talking about 3.03
which is pretty close.

The boiler might be adjusted slighly high on burn rate, but it isn't
substantially over based on gas consumption rate.


Have I worked this out correctly?

If I HAVE worked it out correctly I what else could I look at next - just
checked the metre and I only have used £4.20 in gas since 3:30pm yesterday.

Assuming your 3p scales up and paid for 1.112 gets you to approx the
2.6p/unit you mentioned before. This would imply that you had used
162kWh since yesterday (say 22hrs) and gives an average usage rate, if
it were linear (which it isn't) of 7kW.

Usage depends on heat loss of course. This is proportional to the
difference between the inside and outside temperatures. It becomes
hard to calculate unless you were able to record the outside
temperature say hourly during the day and night and thus calculate
apportioning the usage. Even so, it doesn't tell you a great deal.
With setting back the temperature to 16 degrees over night you reduce
the heat lost compared with if you had left the thermostat at 20 or 21
degrees. On the other hand, the outside temperature is lower at night
anyway.




We have not used any hot water (apart from a couple of hand wash basins
full) and the heating has been set to 16degrees overnight. I am wondering if
there might be a problem with the gas fire which is in the lounge?

This seems doubtful. You could repeat the meter exercise with just
the fire and see what it's using. However, they are rated at
typically 3-5kW so it is not likely to be a big factor - plus it's
heat into the room anyway.


Based on what you've said, it doesn't sound as though the boiler is
firing incorrectly or that the meter is reading incorrectly in terms
of measurement of gas volume.

This really leaves two things:

- Insulation of property is such that a lot of energy is being used
because of heatloss. This depends on size and construction of
property. What is it? How old? Are the walls solid brick or cavity?
Double glazing?

- Charging of usage. I think you mentioned that the tariff is at one
price for the first N units and a lower price for the rest. Could it
be that it charges at the high rate always and you get a rebate when
they empty it or subsequently? I can remember many years ago a
relative having a coin meter. The gas board guy would come and empty
it and give them some money back based on the tariff.
Do you have the option to switch to a quarterly meter and a better
tariff?


--

..andy