Sudden increase in gas usage/consumption

[Gas user person username]

Hi. My gas usage suddenly increased massively overnight. I'm not talking about the cost, but the actual usage. Below shows how long I had the heating on and what the gas usage was in kWh:

Date | heating duration | usage (kWh)
16/11/22 | 2h 18m | 15.64 kWh
17/11/22 | 2h 51m | 16.81 kWh
18/11/22 | 3h 23m | 21.36 kWh
19/11/22 | 3h 15m | 21.18 kWh
20/11/22 | 1h 59m | 14.54 kWh
21/11/22 | 6h 16m | 38.77 kWh
22/11/22 | 2h 52m | 74.55 kWh
23/11/22 | 3h 30m | 79.50 kWh
24/11/22 | 2h 20m | 63.56 kWh
25/11/22 | 1h 45m | 48.51 kWh
26/11/22 | 1h 44m | 44.11 kWh
27/11/22 | 1h 15m | 34.72 kWh
28/11/22 | 4h 35m | 107.00 kWh

Aa you can see there is an enormous jump in usage between the 21st and 22nd. It doesn't appear to be a constant increase everyday, it looks like an increase in the rate that gas is being consumed for the central heating. There's no issue with hot taps or anything like that as there is no gas usage when the heating is not on.

Any advice would be great as British Gas and Google just keep trying to tell me that everyone's bills are going up which is obviously not the issue.

Thanks

 

[SimonG]

Wheres your boiler located? Does it have a frost stat?

 

[Deleted member 120897]

What boiler make/model? Preheat on?

 

[snowhead]

Is the heating temperature setpoint,,
the same over night and day (24hrs) ?
or does the setpoint vary at different times of day ?
or does the heating go off altogether during some periods in the day and or night?

And is it a modulating boiler?

 

[Gas user person username]

Thanks for the replies.

Boiler is a Worcester Greenstar 8000 Style.

My "heating on" number refers to times the heating was actively on. We have a Hive which we have on schedule for an hour in the morning targeting 18° which is typically always heating for the full hour. We also manually turn the heating on via the Hive at times throughout the day. The heating times are read ours directly from the Hive where the heating is actively on.

Preheat is off on the boiler.

Frost protection is on.

I'm skeptical it's anything to do with preheat or frost protection as the increase occured without changing any settings and is not consistent everyday. It appears the actual rate of gas used per hour of heating has increased.

 

[Chuck]

To save everybody the pain of doing the same calculation, here's the OP's data with the mean boiler power added as the last column:

16/11/22 | 02:18 | 15.64 kWh | 6.8 kW
17/11/22 | 02:51 | 16.81 kWh | 5.9 kW
18/11/22 | 03:23 | 21.36 kWh | 6.3 kW
19/11/22 | 03:15 | 21.18 kWh | 6.5 kW
20/11/22 | 01:59 | 14.54 kWh | 7.3 kW
21/11/22 | 06:16 | 38.77 kWh | 6.2 kW
22/11/22 | 02:52 | 74.55 kWh | 26.0 kW
23/11/22 | 03:30 | 79.50 kWh | 22.7 kW
24/11/22 | 02:20 | 63.56 kWh | 27.2 kW
25/11/22 | 01:45 | 48.51 kWh | 27.7 kW
26/11/22 | 01:44 | 44.11 kWh | 25.4 kW
27/11/22 | 01:15 | 34.72 kWh | 27.8 kW
28/11/22 | 04:35 | 107.00 kWh | 23.3 kW

 

[Mario1]

Thanks for the replies.

Boiler is a Worcester Greenstar 8000 Style.

My "heating on" number refers to times the heating was actively on. We have a Hive which we have on schedule for an hour in the morning targeting 18° which is typically always heating for the full hour. We also manually turn the heating on via the Hive at times throughout the day. The heating times are read ours directly from the Hive where the heating is actively on.

Preheat is off on the boiler.

Frost protection is on.

I'm skeptical it's anything to do with preheat or frost protection as the increase occured without changing any settings and is not consistent everyday. It appears the actual rate of gas used per hour of heating has increased.

Hi, did you ever get to the bottom of it? I'm having the same issue. We had a 30+ year old boiler and replaced it a couple of weeks ago thinking maybe the boiler was not efficient and using too much gas. But with a brand new boiler the usage is still high. I've just been through the last few years of bills and found that we were averaging 50kwh per day for years and then suddenly a couple of years ago it jumped up to 300kwh per day. At the time, the gas prices were so low I never looked in to it. But with the price hike now it's completely unaffordable so it's forced me to investigate and we're somehow using enough gas to heat 10 average UK homes.

 

[John.g]

Are you and the other gas user actually reading ths gas meters now and then, you can X the m3 by 10.9 to give the usage in kwh. the conversion factor should be in your gas bill.

 

[John.g]

To save everybody the pain of doing the same calculation, here's the OP's data with the mean boiler power added as the last column:

16/11/22 | 02:18 | 15.64 kWh | 6.8 kW
17/11/22 | 02:51 | 16.81 kWh | 5.9 kW
18/11/22 | 03:23 | 21.36 kWh | 6.3 kW
19/11/22 | 03:15 | 21.18 kWh | 6.5 kW
20/11/22 | 01:59 | 14.54 kWh | 7.3 kW
21/11/22 | 06:16 | 38.77 kWh | 6.2 kW
22/11/22 | 02:52 | 74.55 kWh | 26.0 kW
23/11/22 | 03:30 | 79.50 kWh | 22.7 kW
24/11/22 | 02:20 | 63.56 kWh | 27.2 kW
25/11/22 | 01:45 | 48.51 kWh | 27.7 kW
26/11/22 | 01:44 | 44.11 kWh | 25.4 kW
27/11/22 | 01:15 | 34.72 kWh | 27.8 kW
28/11/22 | 04:35 | 107.00 kWh | 23.3 kW

If the DHW demand is stripped out you will probably find that the difference is mostly due to changing outside temperatures, assuming required house temp of 20C, if the ambient temperature changed from say 10C to 0C, then the consumption will increase by a factor of 2 or 100% increase since we are told that heat loss is linear.