Boiler gas usage

[Breesey]

My folks moved into a bungalow a year ago having lived in a large house for the previous 25 years. This bungalow is cavity and loft insulated and is heated by a potterton Profile 60EL (17.6Kw) non condensing boiler which is about 7 years old (? possibly less) via 8 rads. The boiler was serviced when they moved in and has apparently been running perfectly since.

They were recently surprised by their gas usage, as it compared with their old house, as they expected, for obvious reasons, that it would be less than their previous big old house. They run the heating/HW in a 'standard' kind of way ie the place is kept warm, not hot, on a twice-a-day programme, they use the shower twice at most each day, other hot water use is also standard.

The gas usage is, on average, about 11 units per day (high?). Assuming correct boiler operation could this high usage be down to the fact that the boiler is over rated for the property and is not able to modulate its power output down low enough for the requirements? ie it burns as much gas for low demand as it would if more heat was called for, getting rid of the unrequired extra heat out through the flue.

Would a lower capacity 13Kw condensing boiler make a significant difference?

Any thoughts much appreciated

 

[JonB]

Dear Breesey
That sounds very high, I am a pensioner and have the heating on 8.30 AM
until 10.30 PM seven days a week. I check all my meters every monday morning the gas runs on average 2.3 units per day.
We have a Ferroli 102 Modena Combi boiler running 8 rads.

Sounds like it needs checking over, & start saving for a bigggg bill.

JonB

 

[Breesey]

Thanks for that Jon. Is yours also a well insulated bungalow? I wonder whether this is a case for the leave-the-heating-on-at-a-sensible-level-all-day-is-best argument!

Any more technical comments most welcome!

 

[JonB]

It is a well insulated 3 bed semi & cavity wall insulation.

JonB

 

[pierrot]

are you sure its not the huge price increases in gas that have been feeding through the last 18 months.

 

[peewee2]

Our central heating is on 24/7 and we average about 5 units a day. Our boiler is a Ferroli Falcon combi-bolier and we have eight radiators covering a three storey terrace house.

You also need to check if the units are imperial or metric as we might not be comparing like for like (check the meter).

 

[JohnD]

How thick is the loft insulation? A bungalow will have a relatively great area of loft for heat to fall out of.

Rooms stat and TRVs?

Does the bungalow have a lot of glass, picture windows, french windows etc?

oh yes - and it doesn't have a gas fire, especially gas coals?

 

[Soggy_weetabix]

long shot, but has a chip shop opened up recently next door?

David

 

[Breesey]

Thanks for the replies.

Pierrot: I am talking about quantity not price here.


PeeWee2: Do you just leave the stat at X degrees and let it get on with it? They have a digi meter btw.

John: They have 75mm loft insulation. There is a double patio door and a fair bit of glass. I would say that the window area is above average. There's a room stat in the hall and TRVs. They do have a gas fire in the lounge, I don't think its a gas coal fire though, in any case it is rarely used.

Soggy: I checked and... No. A long shot as you said but good thinking

 

[Breesey]

Could a high burner pressure significantly affect consumption?

 

[peewee2]

We tend to set the thermostat to 22 degrees celsius during the day and then turn down to 18 degrees during the night.

 

[JohnD]

That loft insulation would benefit from at least doubling. New houses have a ludicrously deep layer. There are often discounted rates for insulation available from the gas and electricity companies, esp. for retired people.

I see the walls are already done.

 

[croydoncorgi]

Best thing to do is to time the gas meter when only the boiler is operating (make sure the burner is actually operating). Time it for 1 cuft or 0.1 cu meter of gas, in seconds, and report the answer here. Someone will quickly tell you whether the boiler is burning at the right gas rate. Having checked that, it's then worthwhile to look at other reasons for high usage.

 

[Breesey]

Best thing to do is to time the gas meter when only the boiler is operating (make sure the burner is actually operating). Time it for 1 cuft or 0.1 cu meter of gas, in seconds, and report the answer here. Someone will quickly tell you whether the boiler is burning at the right gas rate. Having checked that, it's then worthwhile to look at other reasons for high usage.

OK will do


Cheers for all the other replies.

 

[jimbox]

Our central heating is on 24/7

So it's YOUR fault global warming is getting worse...

Ever thought of buying a nice thick duvet and turning off the heating at night?!