Gas usage quadrupled?

dharm999

Just noticed today, when taking a reading that my gas usage has quadrupled in the last two weeks from 1.5m3 a day to over 6m3, which doesn’t make sense given that we only use gas for hot water at the moment, and that hasn’t changed in the last two weeks.  Does this indicate a likely problem with my boiler or could there be a leak somewhere, if so, what’s my next step?

Thanks

JamesO

from an engineering view the easiest option would be if you can cope with not using hot water for a couple of days (boil the kettle) and isolate the gas to see if the meter keeps increasing when you know there's no usage. 

Then check if there's anything accidentally turned on that shouldn't be and if it's not you then it's got to be somewhere in the system - so call a plumber. you should smell if there's a big leak somewhere obvious but it's a health risk as much as a money risk so don't ignore until you can trace why it's happening to your satisfaction. 

WiserMiser

Switch off the supply using the lever or knob next to the meter on the wall.  Electronic and smart meters can misbehave and increment when there's no flow, as a lengthy thread demonstrated, but it's very unlikely that an old-style bellows meter will suddenly over record.

If the reading stays the same with the supply switched off, turn off the electricity supply to the boiler.  If the reading still increases then it suggests a leak.  I assume you don't have a gas cooker, gas fire etc.  You need someone on the Gas Safe Register, not a plumber.

Don't rely on being able to smell leaking gas.  It could be leaking under the floor and building up elsewhere, e.g. in the cavity wall space.

MWT

dharm999 said:

Just noticed today, when taking a reading that my gas usage has quadrupled in the last two weeks from 1.5m3 a day to over 6m3, which doesn’t make sense given that we only use gas for hot water at the moment, and that hasn’t changed in the last two weeks

Have you actually turned off the gas central heating?

Over the last couple of weeks we were surprised to notice that despite generally warm days, it was getting cold enough at night for the heating to come on again...

FreeBear

dharm999 said:

Just noticed today, when taking a reading that my gas usage has quadrupled in the last two weeks from 1.5m3 a day to over 6m3, which doesn’t make sense given that we only use gas for hot water at the moment, and that hasn’t changed in the last two weeks.  Does this indicate a likely problem with my boiler or could there be a leak somewhere, if so, what’s my next step?

1.5m² is about 16.5kWh, which is a lot for a single day unless you have a large household using a lot of hot water (for comparison, I'm using an average of 14kWh per month for hot water). Enabling eco mode on your boiler (if a combi) and turning down the temperature will help to reduce your gas consumption.

6m² (or about 67kWh) would be enough to run the central heating for a day in a small home during winter. First step would be to check how often the boiler is firing up during the day. Check to make sure taps are not leaking. Turn off the gas at the meter for a day or three and see if readings still increase. If they don't, you need to call a Gas Safe engineer in to check the boiler & pipes. If the readings increase whilst gas is turned off, call your supplier and tell them that you have a faulty meter.

Scot_39

Firstly if you suspect any sort of gas leak - any hints of gas odour - it's maybe worth getting the system checked over.

But it could be a faulty boiler, faulty water system, faulty meter or maybe worst case scenario a gas leak.

Did I miss you saying if boiler a combi or a hw tank based system ?

Anyway 6m3 is c67 kWh - a lot even for winter heating.

That's enough to heat several 100 l of water - like my small 120l hot water tank 5 to 6 times daily from cold.  Or more like a months energy use to heat it for normal occassional use (it doesnt feed my 9kW electric shower).

67 kWh - that's also a noticeable level of boiler activity if real.  About 2-3 hours on full burner power for a smaller domestic model that tend to be rated in the 24-30kW range. Longer in reality as most derate after initial cold start.

And lastly domestic gas smells - deliberately mixed with a strong chemical with sulfury smell (bad eggs) - and even small internal leaks smell pretty foul to many people - but not everyone.

So where is your meter physically - inside or outside ?

If outside are there any signs of excessive deterioration - rust etc 

Does your hot water feel abnormally warm or cold.  

Unless it's flowing out pressure release pipework - on tank or on boiler itself - that's a pretty noticeable water leak if leak above floor / ground level if water side.

We had a fault on a newish combi with closed pressure loop for rads leaking into condensate pipe - trickle flow rather than dripping was the service engr description on phone.

It's been a bit cooler overnight recently - 3C here at 5 am this morning according to met office - damp on cars et - and my sisters heating has been triggered a couple of times overnight set for 15C.  So rads still warm as she gets up.

BUT I'd really expect you to notice if 67 kWh was real heating.

Had one report here of one boiler firing on faulty frost protection even at 19C mid day - not noticed as in a garage - keeping use high.  But probably - nowhere near as high a kWh energy use as yours.


Do you have a smart meter and access to 1/2 hrly reads - if so what's the distribution of those kWh - and at times when know when not using hw or using heating (if).


But given the energy level could also indicate meter fault or perhaps just a gas leak your side of it too.

There a thread here about 1 meter type that was reading on low pressures and so when isolated too.

https://forums.moneysavingexpert.com/discussion/6452074/gas-meter-still-increasing-whilst-gas-isolated-siemens-landis-gyr-e6s

You could try the off off test - Switch the supply and boiler off for a day or even several hours / half a day if possible should be noticable given 6m3 daily - and see if meter still increments.

Or Switch boiler off but leave gas supply on and see if meter still increments

dharm999

MWT said:

dharm999 said:

Just noticed today, when taking a reading that my gas usage has quadrupled in the last two weeks from 1.5m3 a day to over 6m3, which doesn’t make sense given that we only use gas for hot water at the moment, and that hasn’t changed in the last two weeks

Have you actually turned off the gas central heating?

Over the last couple of weeks we were surprised to notice that despite generally warm days, it was getting cold enough at night for the heating to come on again...

Definitely off, as it’s switched off at the controller

dharm999

So, latest is have spoken to my trusted plumber, who thinks it may be a valve or wiring.  I noticed the pressure had dropped, so increased it back to 1 bar at his suggestion.  Have switched off the boiler completely, and only other gas usage will be from the hob.  Have taken a gas reading, so will monitor it from now, to see if it increases.  We have an old style gas meter, so no issues with a problem with an electronic one, but that’s not to say there isn’t a problem with the existing meter.   Have found out we don’t have an immersion switch in the Megaflo so will have to switch the boiler back on when we need hot water.

Thanks to all who commented so far.  No smells of gas.  Meter is in the garage, and no signs of rust or deterioration.  Boiler is not a combi, oldish ‘normal’ boiler, Greenstar 40CDi Classic Regular.  We bought the house last September, and were told that the exchanger was replaced recently before we bought the house.

dharm999

Forgot to say, that the boiler fires up regularly, when switched on, even when hot water and heating aren’t on, but the house doesn’t have a thermostat anywhere, as there is UFH at the middle level with wall controllers in each room, three storey house, and radiators at the ground and top level.  From a previous thread I posted, the feeling seemed to be that it firing up regularly was normal.

victor2

If the already suggested checks don't reveal anything, take meter readings daily (at about the same time each day), rather than averaging it over a few weeks. Then see what your actual daily usage is.

Is it a combi boiler or do you have a hot water tank?

dharm999

Have a hot water tank, a Megaflo.