[Ancien]

I have noticed that if adding up the 7 days costs of a week - Mon to Sunday - as shown on the IHD that they do not equal the weekly cost as shown on the IHD. In my case, for the week I checked, the 7 day costs for gas were £24 higher than the weekly cost shown. Has anyone noticed a discrepancy between the two.

[Andy65]

Hi @Ancien

I never look at the costs on the IHD myself, but looking at 'last week', my IHD shows a weekly total of £2.12 but I worked it out to be £2.08. I used less than 1kWh so a 4p difference is neither here nor there in my mind because of any rounding up/down, calorific value etc.

For 'this week', I can scroll back to the 4th April but the IHD shows 0, so not even the SC for this day!. From the 5th to yesterday the IHD shows £2.08 for the current week total, but if I add up the individual days (5th to 11th), I get £1.48 - 60p less. The daily costs shown for the 5th and 6th total 60p, so if the IHD week ran from Sun to Sat then mine would be correct, but that may just be a coincidence.

As I'm a low gas user outside of the winter months, I can only realistically check it during winter. If I were you I'd just put it down to the inaccuracy of the IHD, even your bills have rounding up/down whereby there can be a discrepancy between the readings and usage shown. As far as costs go, I think the IHD is a rough guide.

Have you tried looking at 'Last Month' on the IHD and comparing that to your spreadsheet? I've just done that myself for gas and the IHD is 1p different to my spreadsheet for the month, so I'd say the differences you're seeing may be due to lags in populating the data, rounding up/down etc. From a customer point of view though, I would have thought that 'This Week' is the one function that would need to be reasonably accurate, otherwise what's the point?

[WizzyWigg]

Morning @Ancien I'm afraid I've never found the IHD to be 100% accurate. I use KWh as a guide (not the gospel) for daily usage, and calculate costings using meter readings on my spreadsheet.

[Ancien]

Mprning @WizzyWigg, I too have a spreadsheet that I use. I'm just interested to find out if others have the same problem.

[WizzyWigg]

@Ancien
The spreadsheet and manual monitoring is truthfully the best way. It's extremely useful when deciding whether to keep or change tariffs.
Looking around and about I've not come across your problem actually mentioned. IHDs do present numerous problems in various forms.
Is your information just a one off week or have you been able to monitor it over a period of time, (a month or two)? If so are there any times the discrepancy has been less than the total of the 7 actual days?

[meldrewreborn]

@Ancien

Gas costs on an IHD are always an estimate because the conversion from volume to kWh is an inexact approximation built into the meter. Why the addition of 7 days doesn’t equal a week’s total is a mystery.

[retrotecchie]

@Ancien

Not sure how you are doing your calculations but the cost of the gas itself added up over the seven days is not going to be the same as total cost for the week. Does your discrepancy equate to seven days worth of standing charges, combined with the IHD not showing the correct tariff?

[Mailman]

@Ancien

As someone who records daily usage numbers from the IHD onto a spreadsheet the issue you raise has never crossed my radar. I'll check my numbers in the morning 're what the weekly total is actually trying to show. Possibly the totals for week resets at the start of each week so that the only time the weekly will match the sum of the individual daily totals will be once a week. Will confirm with my IHD numbers on Friday at some point.

[Ancien]

@retrotecchie We are not on Pay and Go and e-on have told me that in that case Standing Charges and VAT are included in the IHD figures,

[Ancien]

@Andy65 I do not usua;;y do this but we had not been at home for about 10 days visiting relatives and when I got back I thought I would check it. A discrespancy as large as I found is not something i wotld expect and it started on the 31st March. Subsequent to then there is only pence difference.