Boiler issue, house not warming but gas usage v high

Mickygg

Hello all

I recently moved into a house that is just soooo cold. I can't heat the house above 16 degrees as the boiler overheats and shuts down if I turn the thermostat on the boler past 2out of 5.
The added problem of this is tha I'm currently using 20 units of gas a day, which works out at about £10 a day!!
Does anyone have any advice? The boiler is 20 years old, a potterton profile 80e.
I'm assuming a new boiler would sort me out? I'm not sure how much more efficient new boilers are supposed to be though, I'm told mine is currently energy efficiency F whereas new ones are A.
Thanks in advance.

sniggings

if the boiler was running at full power and still not heating the house then yes a new boiler would be the answer, but as it is only running at less than full power, it may just need a service, I would get it serviced and if it still does not run correctly , you need a new boiler.

keystone

Mickygg wrote: »

Hello all

I recently moved into a house that is just soooo cold. I can't heat the house above 16 degrees as the boiler overheats and shuts down if I turn the thermostat on the boler past 2out of 5.
The added problem of this is tha I'm currently using 20 units of gas a day, which works out at about £10 a day!!
Does anyone have any advice? The boiler is 20 years old, a potterton profile 80e.
I'm assuming a new boiler would sort me out? I'm not sure how much more efficient new boilers are supposed to be though, I'm told mine is currently energy efficiency F whereas new ones are A.
Thanks in advance.

What you seem to be doing is akin to wondering why the car isn't going anywhere despite your foot being flat on the throttle and engine at max chat but unfortunately the car isn't in gear.

You shouldn't be using that control on your boiler to regulate your heating. You should have a control system for the heating including a roomstat and possibly thermostatic radiators valves. Its probably a case of unfamiliarity with how your system should be operated. Please would you describe your system in much more detail. Its far too early to say you need a new boiler based on what you have said already.

Cheers

diywhynot

Mickygg wrote: »

Hello all

I recently moved into a house that is just soooo cold. I can't heat the house above 16 degrees as the boiler overheats and shuts down if I turn the thermostat on the boler past 2out of 5.
The added problem of this is tha I'm currently using 20 units of gas a day, which works out at about £10 a day!!
Does anyone have any advice? The boiler is 20 years old, a potterton profile 80e.
I'm assuming a new boiler would sort me out? I'm not sure how much more efficient new boilers are supposed to be though, I'm told mine is currently energy efficiency F whereas new ones are A.
Thanks in advance.

Upgrade the insulation in your property and have your boiler serviced/ central heating maintenance check before you contemplate replacing your 'Band E' Potterton.

HappyMJ

Mickygg wrote: »

Hello all

I recently moved into a house that is just soooo cold. I can't heat the house above 16 degrees as the boiler overheats and shuts down if I turn the thermostat on the boler past 2out of 5.
The added problem of this is tha I'm currently using 20 units of gas a day, which works out at about £10 a day!!
Does anyone have any advice? The boiler is 20 years old, a potterton profile 80e.
I'm assuming a new boiler would sort me out? I'm not sure how much more efficient new boilers are supposed to be though, I'm told mine is currently energy efficiency F whereas new ones are A.
Thanks in advance.

Your usage would drop from 20 units a day down to about 17 units a day based on the same temperature.

How big is your house and how long do you have the boiler running for? Even on the lowest setting that boiler outputs 17.5kW of heat consuming 23kW of gas.

pinkteapot

Just one thing before you look into replacing the boiler...

Our boiler also has a 1-5 dial on the front (in addition to the central heating thermostat in another room). Our boiler "kettles" if I turn the boiler dial above about 3.5. It comes on, works for a while, then there's a sort of hissing sound and it shuts off. It then comes back on as the heating isn't up to temperature and the cycle repeats.

Is this what yours is doing? You said it overheats above 2...

If it is, it could be due to limescale build-up (as ours is). If this is the case, a gas engineer can put a descaler into your system that should clean it out a bit and then you should be able to turn the dial up higher so the water in your radiators is hotter.

Getting someone in to descale ours is one of those jobs I keep meaning to get round to as our boiler will still run hot enough to provide sufficient heat at the moment.

£10 a day sounds very high. Do you have the heating on all day long? Ours is also a 20 year old boiler, maybe similar-ish to yours in terms of gas usage (Glowworm Economy F). We have the heating on 5:30am-7:30am and 4pm-9pm. At weekends it's also on during the day. Our gas and electricity bill combined for the last three months was £340, or just under £4 a day...

Mickygg

keystone wrote: »

What you seem to be doing is akin to wondering why the car isn't going anywhere despite your foot being flat on the throttle and engine at max chat but unfortunately the car isn't in gear.

You shouldn't be using that control on your boiler to regulate your heating. You should have a control system for the heating including a roomstat and possibly thermostatic radiators valves. Its probably a case of unfamiliarity with how your system should be operated. Please would you describe your system in much more detail. Its far too early to say you need a new boiler based on what you have said already.

Cheers

Hi keystone


Yes I know I shouldn't but if I turn it up any more it overheats and shuts down. I have a room stat which is turned to 20 degrees but never reaches this. I have the boiler control on 2 and even that makes the front of the boiler seriously hot.
The boiler is heating 14 rads. Heats them all up fairly quickly. I think your right with your car analogy.

Mickygg

HappyMJ wrote: »

Your usage would drop from 20 units a day down to about 17 units a day based on the same temperature.

How big is your house and how long do you have the boiler running for? Even on the lowest setting that boiler outputs 17.5kW of heat consuming 23kW of gas.

It's a 3 bed but 3 reception rooms, all pretty large (well by my previous new build standards anyway!). I usually have boiler on for 2 hours am and 6 hours pm. I had boiler on for 6 hours last Thursday then on for 12 hours Friday in desperation to try to heat house up and I used 38 units in total! I'm flabbergasted.
The radiators seem to be pretty hot, but the boiler almost always on but house not warming up.

closed

turn off in rooms not used, shut doors, fix draughts, use thick curtains, check loft and hatch insulation, bleed radiators, set thermostats appropriately especially trv's.

18 hours of hot radiators and 430kwh (assuming your readings are metric) or heat should warm any house, the fact they are hot suggests the boiler is doing it's job.

Mickygg

pinkteapot wrote: »

Just one thing before you look into replacing the boiler...

Our boiler also has a 1-5 dial on the front (in addition to the central heating thermostat in another room). Our boiler "kettles" if I turn the boiler dial above about 3.5. It comes on, works for a while, then there's a sort of hissing sound and it shuts off. It then comes back on as the heating isn't up to temperature and the cycle repeats.

Is this what yours is doing? You said it overheats above 2...

If it is, it could be due to limescale build-up (as ours is). If this is the case, a gas engineer can put a descaler into your system that should clean it out a bit and then you should be able to turn the dial up higher so the water in your radiators is hotter.

Getting someone in to descale ours is one of those jobs I keep meaning to get round to as our boiler will still run hot enough to provide sufficient heat at the moment.

£10 a day sounds very high. Do you have the heating on all day long? Ours is also a 20 year old boiler, maybe similar-ish to yours in terms of gas usage (Glowworm Economy F). We have the heating on 5:30am-7:30am and 4pm-9pm. At weekends it's also on during the day. Our gas and electricity bill combined for the last three months was £340, or just under £4 a day...

No not really. Mine works as normal, but then turns off and I have to press the reset button to get it going again. The v old instructions say this is due to overheating.
I'll look into the descaling, thanks.
No as in my post I've just done above usually 8 hours a day, so same as you. Thanks for the bill info, that helps as thats more what I'd expect but I'm looking at £180 just for the last months gas usage as I've used just under 400 units!!
From that something has to be wrong.


Thanks all for your responses, I'll look into getting a service done, descaling and also may try my gas provider to see if they will check the meter. When the gas is on you've never seen something fly round so fast.

Mr_Ted

Mickygg wrote: »

I can't heat the house above 16 degrees as the boiler overheats and shuts down if I turn the thermostat on the boler past 2out of 5.

This would indicate a lack of flow through the boiler, check pump and motorised valves are working correctly, there is possibly a restriction somewhere that is preventing full temperature from reaching the system?

Unlikely to be scale on a heating only boiler as scale build up requires a regular fresh water flow through the system, a heating system does or should not get this unless you have had to change or top up the water many times!
Other option is a heat exchanger that is clogged on the combustion side, but I would check the flow problem possibility 1st?
Could also be the dreaded sludge or magnatite problems of which there is plenty of discussion about on here!