How much KW of gas does your combi use per hour?

Gerry1

Coffeekup said:

JohnSwift10 said:

I use approx 67 kWh of gas a day for a 3 bed semi with the heating on all day from 07:45 to 23:30 with about 20 - 30 kW of gas used in the first 2 hours, to raise the temperature up to 21 deg C from whatever it has dropped to during the night when the heating was off and a couple of showers.

Then the heating kicks in every so often during the 13 3/4 hours  left in the day, about 2 - 3 kW every hour until 23:30.

Your house must be nicely insulated, in your case it'll be cheaper to never have the heating turned off

That myth just keeps coming back...

JohnSwift10

Coffeekup said:

JohnSwift10 said:

I use approx 67 kWh of gas a day for a 3 bed semi with the heating on all day from 07:45 to 23:30 with about 20 - 30 kW of gas used in the first 2 hours, to raise the temperature up to 21 deg C from whatever it has dropped to during the night when the heating was off and a couple of showers.

Then the heating kicks in every so often during the 13 3/4 hours  left in the day, about 2 - 3 kW every hour until 23:30.

Your house must be nicely insulated, in your case it'll be cheaper to never have the heating turned off

I used to think that but not now.

When I go out I turn the thermostat off.

Yesterday after being out for 4 hours when I came home the temperature in the lounge had dropped to 17.5 deg C from 20.9 deg C, the upstairs to 20 deg C 

I have a raspberry pi that records the time and temperature to a spreadsheet every 10 minutes.

It only took 30 minutes to bring the temperature up to 19.9  deg C when the heating switches off and the residual heat in the radiators raise it another degree.

If only my smart meter could became smart again.

Boxman

3 bed not particularly big detached house, Baxi combi boiler, 91% Sedbuk rating plus gas fire in living room.  When min overnight temp drops to zero or slightly less have found we generally use about 75kWh in 24 hours.

In July and August with no heating, hot water plus gas hob usually use around 4 kWh per day.

northernsoul

2 bed + attic terraced house in Yorkshire. No insulation apart from 2 inch kingspan on ceiling in attic.

Vaillant 837 (11 years old) 28kw boiler set at 62C. Thermostat set at 18C , on at 07:00 and off at 22:00 (15 hours total). Upstairs is kept at 16C , downstairs 18C. Attic radiator set at frost (5C)

8 radiators. total output 13.9kw (when all used)

On 22-12-2021 with day temperatures about 1C and house at 07:00 14C , used 11.39kwh (£0.45 of gas) first hour , then 4.06kwh the second hour when it reached the 18C target. Every hour afterwards used less and less gas until the final hour used 2.59kwh (£0.10).

A total of 56.72kwh (£2.23) used.

Day after , everything the same apart from house temperature at start 15C and day temperature about 5C , used 48.38 kwh (£1.91)

QrizB

1950s 3-bed semi, 4 occupants, gas CH, HW & stove. Average gas usage in each of Nov and Dec 2021 was 30kWh/day.

Summer usage varies but is around 6-8kWh/day.

My worst ever month with actual meter readings (not estimates) was 60kWh/day.

Regular boiler, not combi - a 2005 18kW Worcester Bosch Greenstar.