Boiler inefficiency- cause and fix??

[Looking4help]

Hi, moved into a home a year ago with what is probably an old heating system. There is a gas boiler linking to radiator central heating, and a water tank.

Energy company charged an enormous amount for gas last winter (admittedly I hadn't taken regular meter readings so was unaware until a huge bill arrived).

I have been tracking gas meter readings more regularly over the last six months or so, it seems the hot water is quite efficient, using around one unit of gas per day for typical use, cost about £1.50 per day. However, started putting the heating on this week and shocked to see the cost c£60 for one night of heating (not an excessively warm temperature, and only on overnight).

My thinking is that the meter is probably not the issue if hot water is running efficiently, so it has to be the heating.

So why would the heating be using huge amounts of gas, when the same boiler heats the water efficiently?? Any ideas?? I will be getting professional help but want to know what to ask for I.e. would a boiler service help? Or does it need something fixed or worse replace the whole thing?

Concerned about throwing good money after bad so don't want to pay for a service and/or quick fixes and just end up replacing it anyway.

Advice much appreciated!!

 

[ShaunCorbs]

200kwh

Say the boiler is 30kw that’s 7 hours of full usage

Need more information

 

[Desktop987456]

How did you calculate GBP1.50/day for HW and GBP 60/day for heating?

 

[ShaunCorbs]

It’s 30p a kWh so divide 60 by 30p = your kWh then divide that by the boiler kw gives you roughly the burn time

 

[Enthalpy]

Under the Energy Price Cap rates from 1 October to 31 December 2023 gas costs about 6.89 pence per kilowatt hour (kWh). Therefore £60 corresponds to about 870 kWh or 36 kW continuously for 24 hours.

Perhaps there is confusion about units.

Gas is metered in units of cubic metres (m3) and billed in units of kilowatt hours (kWh).

Energy usage is calculated from gas consumption using a standard industry formula:

• Units Consumed (Cubic Metres)
• × Volume Correction (for temperature & pressure)
• × Calorific Value (energy in each m3 of gas)
• ÷ 3.6 (convert from joules)
• = Usage (in kWh)

Volume Correction and Calorific Value can be found on your gas bill. Using typical values:

For 1 m3: 1.0 × 1.02264 × 39.8 ÷ 3.6 = 11.13 kWh

Therefore 1 m3 of gas provides about 11.13 kWh of heat and costs about £0.77.