Smokeless Coal in Multi Fuel Stove doesn’t warm the room?

sourlemons

Hi all, 

Looking for some advice from seasoned smokeless fuel users please! 

Got a multi stove fuel installed a week ago, 8kw double door so it’s quite roomy inside and my plan is to burn smokeless coal as the main fuel. Installer suggested an 8kw would be ample for the room size which is draughty anyway, open plan living/dining room. 

Anyway, gave it a whirl last night and boy was I disappointed! I started it at 5pm and the temperature on the flue thermometer didn’t get above 100 degrees Celsius, never mind optimum burn range. The stove fans I have were whirring away quite quick after lighting but honestly, I was still cold in the room. At 10pm, I gave up and went to bed. 

It is my first multi fuel stove but I’ve done lots of research about when to open primary/secondary vents (I’m leaving door ajar when getting the kindling going, all vents open and then when it got a good burn going, adding 5/6 lumps of coal, closing the door, closing air wash whilst keeping bottom two vents fully open for air flow) once the coals were burning red underneath, I continued to add more lumps of coal and continued to do so (wasn’t quite sure when to stop to be honest!) By the end, I had almost filled the whole grate with 2 layers deep of coal.  

By 10pm, there were lovely, slow blue flames, all the coal were now hot and ashy and it was still burning strong but just no heat radiating out into the room and still sitting at 100 Celsius. The coals were wet (I didn’t have enough patience to wait until they dried!) would this have made a difference? I don’t have a coal bunker, or anywhere to dry coal really when they come wet from the bag so will probably use it as it is- is this a problem? 

My question is, was it because I didn’t add enough coal which is why it didn’t get up to a higher temperature? Is 100 degrees a normal temp for it to stay consistent at because I really wasn’t feeling the benefit of the stove if it is… 

I spent a couple of hours watching YouTube videos but I still don’t know where I went wrong so thought I’d try getting advice on here. Any tips would be appreciated. 

Thanks so much! 

FreeBear

sourlemons said: The coals were wet (I didn’t have enough patience to wait until they dried!) would this have made a difference? I don’t have a coal bunker, or anywhere to dry coal really when they come wet from the bag so will probably use it as it is- is this a problem?

Do not ever burn wet coal (or wood). Much of the energy produced is being used to dry the fuel out - It also has the potential to reduce the lifespan of your flue. The water will condense out as it travels up the flue, combining with the sulphuric & nitrogen compounds in the  smoke to produce acid.

Store your coal (and wood) in a dry ventilated area. If you don't have somewhere suitable, I suggest you invest in a shed.

I use smokeless coal in my stove - Whilst it doesn't produce as much heat as wood, it does keep the room warm. I also invested time & effort in plugging all those nasty draughts in order to keep the heat in.

Do not ever burn wet fuel.

ThisIsWeird

Where's the flue therm fitted? Is it single skin at that point?

sourlemons

ThisIsWeird said:

Where's the flue therm fitted? Is it single skin at that point?

Flue therm is just above the flue collar and it is single skin

twopenny

Put the'coal' somewhere to dry out. 
Bodge up an old fashioned dustbin, drill holes, raise on bricks etc. Stack it somehow near the burner in an attractive receptacle. Stacking wood in a fireplace or coal in scuttles a
Is not just for convenience.

Wood should be bought the year before and allowed to dry out using unless already a year old.

Summer coming(so they say) and time to get next winters fuel in and dried.
Also when I had an open fire or log burner it took some time, as in 2 or 3 hrs to really produce heat. Not so great when you're working!! But glorious weekends or if kept in overnight.

FreeBear

twopenny said: Wood should be bought the year before and allowed to dry out using unless already a year old.

Had a pile of logs delivered at the weekend for winter 2024/5. Currently half way through cutting and splitting them - Got a few big lumps of oak in the pile with fresh green shoots sprouting out the sides. Quite likely that it will take at least three years to dry down to 20%. Will pop a couple of bits in the shed to bake over the summer...

John_the_Boy

I have a 7Kw single door inset and find to get a hot fire (170 C with the stove thermometer on the top of the stove) I have to load the stove with about 6kg of dry smokeless at the start. I don't need to top up as this will last from 6PM to 12 PM or beyond.

My questions are....
1. Are you using enough smokeless?
2. Are you getting the smokeless roaring away before you turn the vents down.
3. Are you turning the vents down enough once the fire is well away otherwise you will find the heat goes up the flue rather than heating the stove.

It does take a good few fires to learn what works for your stove. Good luck.

sourlemons

John_the_Boy said:

I have a 7Kw single door inset and find to get a hot fire (170 C with the stove thermometer on the top of the stove) I have to load the stove with about 6kg of dry smokeless at the start. I don't need to top up as this will last from 6PM to 12 PM or beyond.

My questions are....
1. Are you using enough smokeless?
2. Are you getting the smokeless roaring away before you turn the vents down.
3. Are you turning the vents down enough once the fire is well away otherwise you will find the heat goes up the flue rather than heating the stove.

It does take a good few fires to learn what works for your stove. Good luck.

Thank you so much! I think my problem is that I’ve not been using enough smokeless, just adding a few lumps here every so often… noted about the vents as well, thanks! 

I’ll keep persevering, luckily it’s getting a bit warming now so I’ve got time to practice! 

FreeBear

You want to be adding a shovel full or two at a time.

Another thing with burning wet fuel - The glass will blacken quite badly, and can be a real pig to clean. After leaving the stove to cool down, I give my glass a spray with Mr Muscle oven cleaner, leave for 10-15 mins, and then wipe down with a damp sponge. Don't use an abrasive cleaner or scouring pad.

John_the_Boy

I actually find it easier to get a good fire going by putting my kindling and a firelighter at the bottom on the grate then put my 6KG of smokeless on top leaving a gap to get to the firelighter. I then light the firelighter and leave the door ajar for 5 mins until the kindling is well alight and then close the door with the vents fully open until the fire really gets going. Takes about an hour until I fully close the main air vent after that I don't need to touch the fire apart from the occasional riddle.

I guess everyone has their way that works best LOL

Completely agree re damp fuel, the glass is awful to clean. With dry fuel I can wipe the cool glass with damp kitchen towel and the light muck comes away easily.

One tip I was told - when the fire is on, have the smokeless for the next day in a coal bucket on the hearth drying out further. 

Ectophile

HG Stove Glass Cleaner is nasty corrosive stuff - wear rubber gloves.  But it's really good at removing tarry brown stains from glass.

I use it with an old washing up sponge, and lots of kitchen towel to wipe away the mess.