Unsure about kWh

JessandJon_3

 Thank you so much for your help.  I’ve spent the night awake worried so your replies have really helped me understand it more.  I’ll do a meter reading this evening, put the heating on till it gets to 16deg and then read again. 

I’ll also have a look and see how to change the flow settings on the boiler as know this was set by the engineer so may not be at the correct setting.

[Deleted User]

Hi,

not sure if 16 will give you the desired heat, usage will be higher to start with, until room heats up, then should level out.

Have you TRVs on radiators to control heat in each room?

Gerry1

A gas fire is less efficient than a modern boiler (correctly set up so that it condenses) so best not to replace it.

Bigger radiators might be a better solution if the existing ones are too small.

Phlik

JessandJon_3 said:

 Thank you so much for your help.  I’ve spent the night awake worried so your replies have really helped me understand it more.  I’ll do a meter reading this evening, put the heating on till it gets to 16deg and then read again. 

I’ll also have a look and see how to change the flow settings on the boiler as know this was set by the engineer so may not be at the correct setting.

Put it on for at least 24hrs and measure across that time scale, the shorter test you do the less accurate your information will be as the first few hours will be when it uses the most gas so will skew the readings.

[Deleted User]

Phlik said:

JessandJon_3 said:

 Thank you so much for your help.  I’ve spent the night awake worried so your replies have really helped me understand it more.  I’ll do a meter reading this evening, put the heating on till it gets to 16deg and then read again. 

I’ll also have a look and see how to change the flow settings on the boiler as know this was set by the engineer so may not be at the correct setting.

Put it on for at least 24hrs and measure across that time scale, the shorter test you do the less accurate your information will be as the first few hours will be when it uses the most gas so will skew the readings.

True, but I got the impression from the OP that they had very little idea about how much CH heating will cost them per day.  Even doing it over a 24 hour period, the usage fluctuates from day to day - last 3 days have been 23.79 kWh (very sunny but cold), 42.71 kWh (very dull) and 34.49 kWh (wet) and the variation has been due largely to the amount of sunshine I've had and the outside temperature.  Max thermostat setting has been 18.0C in these 3 days.  Re the warming up period when the CH comes on, agreed for sure.  In just over 4 hours I've used 21.75 kWh and I suspect the remaining 10 hours will probably use about the same.  

Ultrasonic

One way gas fires could work out cheaper if if they're just used to heat one room whilst the rest of the house is cooler. Use of TRVs can achieve the same when using central heating though.

[Deleted User]

With the usual caveats that no two houses or usage are the same, this graph shows our actual usage for yesterday. We have a 24kW boiler with the CH boiler flow temperature set to 60C, and we run it from 06:45 through until 18:00. If heat is needed after 18:00 we fire up a small wood burner. As stated above, modern boilers have a modulation ratio which turns down the maximum boiler output depending on demand. When the demand falls below the minimum output of the boiler, the boiler will cycle on and off. Turning down the boiler flow temperature reduces the amount of cycling: more importantly, pushing flow out at 60C guarantees that the returning flow temperature will be in the condensing band. In sum, it saves gas. The downside is that it takes longer for the house to reach its set temperatures. We have our home set to 18C upstairs and 19C downsides. Our annual gas usage is c.7700kWh/year.

wild666

Gerry1 said:

Much easier to think in terms of a kWh costing 7.28p from 1 April, less risk of getting it wrong by a factor of 10 or 100 !

Don't forget that the price per kWh shown on a bill will need to have 5% VAT added.

When I work out the electric and gas bill I use the figures with VAT added so I don't have to add 5% to the total after calculating the reading it's easier for me that way.