Gas usage with Housewarmer economy 44 boiler

[camerart]

Hi,
I have a Housewarmer economy 44 back boiler 1986. It keeps heating the house and water, so I leave well alone.
I was away for a few weeks, so switched it off, but it has a pilot light. My son read the meter for a week, and the gas consumption was 3 cubic meters. This seems far to much, what do you think?
Camerart.

 

[martygturner]

Is that 3 m3 in a week or 3 m3 over the time you were away ?

You can away turn off the pilot light when you are away, can be a faff to turn back on.

 

[oldbuffer]

1. Are you sure the meter is cubic meters or is it cubic feet?
2. No other gas appliance (e.g. hob) used during the measurement week?
3. Photograph of meter would be useful.
4. A 38 year old back boiler would be lucky to have an efficiency of 50%. You might want to do the cost / benefit calculation for updating to a condensing boiler.
5. A doubt you can get any parts for a boiler that old, so your "leave well alone" approach is very prudent.

 

[Johntheo5]

Hi,
I have a Housewarmer economy 44 back boiler 1986. It keeps heating the house and water, so I leave well alone.
I was away for a few weeks, so switched it off, but it has a pilot light. My son read the meter for a week, and the gas consumption was 3 cubic meters. This seems far to much, what do you think?
Camerart.

Sounds about right, 33 watts/hr, 3x11x1000/7/24

 

[Madrab]

Not really, a pilot light can use anywhere up to 3 m3 a week, size dependent

 

[fixitflav]

Sounds about right, 33 watts/hr, 3x11x1000/7/24

Not with you. 3x11x1000/7/24 = 196 watt (not watt/hr!). For the OP, the 11 is kWh/m3 gas CV.

Seems a bit high, but could be right for a boiler that old. 196 watt is about 1700 kWh/year, total gas consumption typical say 20000 kWh/year.

Also for 3 m3 in 7 days, with a few broad assumptions I estimate pilot jet diameter 0.5 mm, which could be about right.

 

[Johntheo5]

My calcularor was lying, 196 is the correct figure

 

[fixitflav]

My calcularor was lying, 196 is the correct figure

Blame the machine!

 

[camerart]

1. Are you sure the meter is cubic meters or is it cubic feet?
2. No other gas appliance (e.g. hob) used during the measurement week?
3. Photograph of meter would be useful.
4. A 38 year old back boiler would be lucky to have an efficiency of 50%. You might want to do the cost / benefit calculation for updating to a condensing boiler.
5. A doubt you can get any parts for a boiler that old, so your "leave well alone" approach is very prudent.

HI O,
Here's the 2x photos.
28-08-24 and 04-09-24
C

 

[camerart]

Hi,
My son took those photos, so today I'm starting to check again.
With only the pilot light, I've read the meter, and I'll check again later, then I'll stop the pilot light and leave it for a day.
C

 

[camerart]

Not really, a pilot light can use anywhere up to 3 m3 a week, size dependent

Hi,
Interesting!
I measured with the pilot light for an hour 0.018/mtr3 XHrs/week 168 =3.024mtr3
I switched off the pilot light for a day and no consumption.

As mentioned pilot lights are a B*****r to light sometimes so I used this:

Thanks all C.

 

[camerart]

Hi,
As mentioned the boiler is fine, but also as mentioned, it isn't efficient.
Where does the inefficiency go?

Anyway, I'm looking at buying a new boiler, but first I'd like to see how long it would take to pay back the cost.

I think my boiler is about 70% efficient. On cold days I light a wood burning stove, using free wood, but don't count this for a calculation. I try not to use too much gas, in a 3x bedroom semi.

Any guesses how long it would take to pay back from the saving?
Cheers, Camerart

 

[Madrab]

Where does the inefficiency go?

A lot of inefficiencies go right up the flue, efficiency it basically calculated as to how much heat translates into the system and then into heating the home rather than is just wasted. Modern boilers have high heat transfer rates and are condensing, that is where they maximise their efficiencies over older boilers.

It would take a long time to re-coup the cost of a new boiler based on that alone but I don't think that's the whole point. It's also about real time expenditure in the present with how much the energy costs now and in the near future.

I do have to add too - there's nothing that's 'free' these days, IMO wood burning stoves are lovely but are a nightmare for the environment.

 

[Johntheo5]

Not sure what the UK gas price is capped at but maybe around 7.0p/kwh?
If you install a new boiler then you should get ~ 88% efficiency even with little or no condensing so a saving of 20.45% on your 70% efficient boiler.
Don't know how much gas you use per year, but assuming the above price at 7p/kwh, then if you use a unlikely 5000kwh/year = £350, saving £72/year, simple pay back on say £2300 for a new boiler + installation, 32years, if you use 10000kwh/annum = £700, saving £143, pay back 16years and if you use 15000kwh/year (like I do) = £1050/year, saving £215, pay back 10.7years. I'm sure someone can give far more accurate numbers than these but you get the rough idea, but doesn't take account of increasing fuel costs over the years.

 

[camerart]

A lot of inefficiencies go right up the flue, efficiency it basically calculated as to how much heat translates into the system and then into heating the home rather than is just wasted. Modern boilers have high heat transfer rates and are condensing, that is where they maximise their efficiencies over older boilers.

It would take a long time to re-coup the cost of a new boiler based on that alone but I don't think that's the whole point. It's also about real time expenditure in the present with how much the energy costs now and in the near future.

I do have to add too - there's nothing that's 'free' these days, IMO wood burning stoves are lovely but are a nightmare for the environment.

Hi M,
Earlier you can see that a pilot light uses app 3m3/week, so in the summer, that's wasted, but as it goes up a chimney, in the cantre of the house, in the winter, I doubt much heat gets out of the chimney pot, so it kind of heats the house.

I try not to use the stove, for that reason, but I used to live in Bradford, and from the moors sometimes only the factory chimnet tops were visible, so things have much improved.
C