Stove smoke > room problem.

[zoothorn]

Hi folks,

 

I have an issue that's now requiring a solution, so bad it is. I have a 10 kW (efel/ nestor martin harmony 1) multifuel stove which has caused endless problems, the single most infuriating currently is smoke pouring into the room when loading it. So much it kicks off the fire alarm, get in your lungs, & causes the house to smell permanently of a veil of smoke. That bad. I have to load up as fast as possible, door a small a gap as possible.. but even still it pours out the front, top (I almost have to wear a mask now). Not so bad once up to speed @ 350*C + due to smoke being burnt off.. but heaven knows what Co its belching out: albeit the Co alarm has never sounded once, thankfully. Once up to speed it works pretty good though.

 

I cannot establish why. I have good draw (visible to see & established so by my very good, very experienced builder). I use all the open functions to aid draw for refueling. Whacking in a new stove is n/a until why has been established.. as it might just do the same.

 

To be honest the stove is a dreadful design, & replacement parts for it terrible quality.. but even so it should -not- belch out smoke like this. My n'bor has a small cheapo chinese horrorshow & a chimney 2/3rds my height.. but not a sign of any smoke coming into room on refueling/ zilch/ just as it should be.

 

Thanks, zootH

 

 

[Declan52]

First thing to check is when you last had the flue swept. 

Have you a flue thermometer?? With one of these you will be able to get the fire box to the correct high temp so it is pushing warm air up and out the top. If it's not at the right temp and you open the door it will drop further and pull the smoke down into the room.

Also don't open the door quick. Open it slightly so the fresh air gets in and then after 20 secs open it and put more fuel on.

How dry is your firewood??? The wetter it is the more smoke you will get.

[jfb]

How much ventilation is getting into the room with the burner? Presumably since it is over 5kw it has a dedicated air vent in the room or a direct air supply?

[zoothorn]

Hi Declan,

 

I recently swept it.. it did this issue the very 1st fire afterwards. Yes I have a thermometer, as I mention its fairly ok once up to speed @ 350*C or above. The issue isn't once its up to speed (tho not great even so) its everything up to this: which means worst is 1st load once innitial small kindling plus smaller load ontop ie 1 or 2 logs slplit into 6 or 8 small bits piled ontop of the kindling. Now if I start just kindling (a log behind & to the sides always) open & load with small split logs once kindling charcoal.. then the smoke is appalling/ I cannot do this. So I have to start it with kindling + a fair stack of small split logs already ontop (+ my large log behind + to eithet side too)  IE a good load to limit the ammount of times I have to open door to reload to get it up to speed. But even so I need to add 2x loads between the innitial load's burnt down & it up to speed. That's twice, minimum, each time I use it, smoke pours out/ alarm goes off/ I have to open all doors windows to clear smoke.. a hopeless situation if its cold outside.

 

thanks for your input- zoot

[zoothorn]

14 minutes ago, jfb said:

How much ventilation is getting into the room with the burner? Presumably since it is over 5kw it has a dedicated air vent in the room or a direct air supply?

 

To be honest jfb its probably got 2x air vents' worth of venting.. as its an older cottage with a few gaps here n there. But nothing excessive, or nothing 'sealed room' to think this makes any difference. If the front door's open for eg, while I start the fire up, its exactly the same as if I close up the vent entirely. No difference whatsoever.

[dpmiller]

Any baffles in the top of the stove that could be distorted or fitted incorrectly?

[Cpd]

Sounds very strange, the only thing I can think of is.

 

1. What size internal flue do you have (is it the correct size for the fire)

2. How high is the chimney from fire to top, roughly to the meter ( short runs can cause issues)

3. How high is the top of the pot from your ridge. (There is a recommended height needed ) 

4. Are you in a location where a micro climate is causing a down draught ( I had this and fitted an anti down draught cowl and it worked)

 

Another option is to borrow someone’s  old stove,,,, I have 3 lying around ! Fit it temporarily and see if it suffers the same problem, if so it has to be flu / chimney / down draught problem. 

 

 

Edited September 30, 2018 by Cpd

[zoothorn]

1 hour ago, dpmiller said:

Any baffles in the top of the stove that could be distorted or fitted incorrectly?

 

Well, I guess it could be distorted.. but how on earth I would be able to establish this I've no idea. It is the original baffle, & I did buy the stove with some prior user OTT heat issues*.. or.. the parts are just terrible quality & not up to par: I say this because I bought a replacement iron front section (with two upright 'prongs' to stop logs hitting glass- another appalling design as you keep nudging it out of place loading in logs as the 2 prongs are so stupidly big & intrusive) which has bowed out of shape like the prior one, within 18 months of normal use.

 

For eg I had to replace the grate, front bit mentioned above, & pan is distorted (but useable).

 

Anyone else have this Harmony 1 multifuel stove? I just cannot believe how many huge design faults I find with it, considering its meant to be a very costly belgian made all solid iron stove, with VG reviews. Its an absolute joke, aside from the current smoke issue (which may well not be its fault).. but replacing it/ an extra £1k I cannot afford, &, may well not be any different re. this smoke issue until I can establish the cause.

[zoothorn]

1 hour ago, Cpd said:

Sounds very strange, the only thing I can think of is.

 

1. What size internal flue do you have (is it the correct size for the fire)

2. How high is the chimney from fire to top, roughly to the meter ( short runs can cause issues)

3. How high is the top of the pot from your ridge. (There is a recommended height needed ) 

4. Are you in a location where a micro climate is causing a down draught ( I had this and fitted an anti down draught cowl and it worked)

 

Another option is to borrow someone’s  old stove,,,, I have 3 lying around ! Fit it temporarily and see if it suffers the same problem, if so it has to be flu / chimney / down draught problem. 

 

 

 

Hi Cpd- it is strange. One thing is definite: the colder the temp is.. the worse the smoke is.

 

1) when you say internal flue, do you mean the width of the ~1m section between the chimney & the stove?

2) 7m. so a good height plus Im the end of a small valley whereby the end of the house with chimney on, gets whacked by wind/ weather: usually I get a vg draw due to this.

3) as the pot is before the ridge relative to the weather coming in, always, due to a west-facing small valley.

4) I do get occasional downdraught, quite considerable, due to probably yes a microclimate in this wee valley.. 98% of the time not.

 

If only I could rule the stove in or out by trying another.. but this is just not possible/ I barely know anyone here/ I'm fairly new, let alone anyone having a spare to lend me. I'm rural you see- plus the only stove fitter not happy with me as my builder chose to install my stove, over ruling him/ not best pleased after his visit aftershave & fancy new stove van et al.

[ProDave]

How is the pipe connected to what I think is a brick chimney?

 

If not well sealed with a closure plate, the draw from the chimney may not be sucking up the bit of connecting flue pipe.

Most stoves are designed for a "warm flue"  If it is an old brick or stone chimney I will bet it has no insulation around it and is anything but a warm flue.

[zoothorn]

@ProDave Hi there- its a 5" flue, 3/4 metre or so in length, with a dog leg 45* elbow just above stove going up & back, 2nd 45* elbow > connecting to > a 10" dia circular pummice-lined chimney all the way up straight 7m, new pot & cowell atop.

 

Pummice-liner was checked as good by my very experienced builder, who installed the stove & flue connecting to it. I think he put a camera/ light down. He also rebuilt my chimney top section/ pot/ cowell/ bird guard atop.

[dpmiller]

what kind of cowl? Was there a HETAS or BC signoff?

[ProDave]

I don't know what to suggest. We had the same problem with the cheap Chinese stove that I put in the static caravan, but that only had a short (2.5 metre) flue. It was alright when up to temperature, so we just learned how to stack it up to get it hot quick without needing refueling before it got hot.

 

But most of last winter it didn't ever go out so this was not an issue.

[PeterW]

@zoothornlooking at the pictures on the web there is some sort of direct draft mechanism at the top, inside back of the stove - is this open or closed..?? 

[zoothorn]

Hi PeterW- there's a door thing (another daft design faux pas IME.. the lever to slide in/out tucks away in the 'in' position around the back/ you have to reach right around the stove, all your body practically ontop of the stove, to get at it.. I want to rip the head off whoever designed it).. but I use to aid draw for refueling, & it does, I think.

 

The baffle looks in good shape, correctly in place & not heat-damaged/ warped at all.. thank gawd.

 

The cowl is a standard terracotta coloured affair I bought on my builders' advice from builders merchants.

 

@dpmiller The whole set-up isn't Hetas or BC signed off, nope, this is wales- you just get things done here (my 40 yr experienced builder, & known as the best around here, as I said installed stove, flue, checked chimney, rebuilt chimney even, put cowl on). It shouldn't affect my solving the problem though.

 

thanks alot for replies/ help chaps.

[Declan52]

Is the stove beside a window???

Could the pull from air leaving via a nearby window be enough to stop the draw up the flue until you get the fire box got enough.

Are you opening the door when it is flaming?? If it has flames it will smoke. If you let the kindling and a few logs burn right down first until they are smouldering. Like you do with a BBQ.

Can you stuff a few pieces of newspaper close to the bottom of the flue to get the flue warmer quicker and get it to draw quicker. Light the paper first then the stack of kindling.

[lizzie]

swap it for another form of heating and do your bit to save the planet....and peoples lungs ?

[Cpd]

3 hours ago, zoothorn said:

 

Had not seen other posts..... questions already asked. 

Edited September 30, 2018 by Cpd

[zoothorn]

2 hours ago, Declan52 said:

Is the stove beside a window???

Could the pull from air leaving via a nearby window be enough to stop the draw up the flue until you get the fire box got enough.

Are you opening the door when it is flaming?? If it has flames it will smoke. If you let the kindling and a few logs burn right down first until they are smouldering. Like you do with a BBQ.

Can you stuff a few pieces of newspaper close to the bottom of the flue to get the flue warmer quicker and get it to draw quicker. Light the paper first then the stack of kindling.

 

 

Ok will try this.. neat suggestion. So you & as ProDave seems to suggest too, seem fairly certain on the cold chimney as cause? IE I should be looking at this rather than cursing the stove itself?

 

Is the larger (say twice vs a steel liner affair) diameter of my chimney any issue? I'm doing complex thought experiments sucking on straws into my milkshake, & different diameters of straws. Rather like Einstein used to do, just on a bit smaller scale.

[zoothorn]

2 hours ago, lizzie said:

swap it for another form of heating and do your bit to save the planet....and peoples lungs ?

 

yes will do.. but hang on I can just walk into the forest & retrieve free fuel yes-? if so, yes sure.. will do.

[PeterW]

10 minutes ago, zoothorn said:

 

 

Ok will try this.. neat suggestion. So you & as ProDave seems to suggest too, seem fairly certain on the cold chimney as cause? IE I should be looking at this rather than cursing the stove itself?

 

Is the larger (say twice vs a steel liner affair) diameter of my chimney any issue? I'm doing complex thought experiments sucking on straws into my milkshake, & different diameters of straws. Rather like Einstein used to do, just on a bit smaller scale.

 Cold brick chimneys take a while to heat up and it could be also leaking - do you run it as a multi fuel or just wood ..??

 

Liner isn’t expensive and it should only take a sweep half a day to drop a liner into the chimney and use a pot hanger to secure it.

 

At the bottom is there just a register plate - a flat plate with a hole in it where the stove pipe enters the chimney ..?

[zoothorn]

I'm not sure it has a register plate, more alot of heatproof wadding secured around the flue > the start of the chimney.

 

But it is pummice-lined though Peter, aparantly according to my builder whose poked his nose down many a chimney, this pummice type is VG if not 'the best' I think I heard him even say.. he was quite adamant I just didn't need to go a steel liner/ heatproof chips affair.

 

But if my builder hadn't taken into account the temp of it when cold/ mine possibly excessively cold to start off with in comparison to a modern liner.. & I can be certain this temp is the cause of my issue, then a liner is possibly the way to go. I need to rule out the other possibles first tho.

 

Am I barking up the wrong tree re. my  big 10" diameter chimney (double the diameter of a 5" steel modern liner chimney) as possible cause?

[Onoff]

@zoothorn, I don't mean any offence but I really struggle understanding some (most) of your posts with their strange abbreviations etc. I have to ask are you actually English by birth?

 

 

[Triassic]

We had a similar problem. We found that moving the flue exit from the rear hole in the stove to the top exit hole cured the problem. Smoke doesn’t like bends it wants to go straight up.

[Cpd]

Strange comment  @Onoff I am probably the least educated person on this forum and have terrible written English but completely understood the posts and what they were driving at. I expect @zoothorn is writing on a bloody tiny phone screen and trying to minimise the the task by keeping things short. Personally I don’t think asking for peoples personal details of where there birth place is (or any other personal details ) has any relevance to this thread and not something I would see as a good thing on this forum as a whole. (No offence intended.)