Chimney fire causes?

[Daniël Bos]

Ok, so in short:
The boiler temperature can have a big impact, but is not likely to be the only issue?

[Stubby]

Years ago we had a chimney fire . It was back when we had an open fire . Swept the flue once a year and always burnt well seasoned wood . Could not understand it . Was not till a few weeks later that the kids admitted to chucking the plastic wrappers from a toy on the fire . It caught alight and floated up and stuck on the top bend .  The fire brigade showed were it was with an infra red camera in the loft . Extinguished it with a hose with a sort of " watering can rose " on the end . Pin point accuracy and no mess .

[MattyF]

Folks have had there esse for 8 years and never had a chimney fire , they only burn soft wood with the occasional large very dead bit of oak to keep it in all night. It does behave very differently with hard Wöod though can get so hot it goes off the temp gauge from when I’ve used it.

[SbTVF]

This may be a daft question but... how does one become aware of there being a chimney fire if you’re sat in the house? Especially minor ones,
aside from the wall potentially setting on fire I suppose?

[Stubby]

11 minutes ago, SbTVF said:

This may be a daft question but... how does one become aware of there being a chimney fire if you’re sat in the house? Especially minor ones,
aside from the wall potentially setting on fire I suppose?

A roaring sound like a jet fighter taking off ...........

[SbTVF]

A roaring sound like a jet fighter taking off ...........

Coming from the chimney stack rather than the stove I assume?

My stove will make that kind of sound on lighting but thats down to the air draw through it while the primary air level is fully open.

[Stubby]

1 hour ago, SbTVF said:

 

 

Coming from the chimney stack rather than the stove I assume?

My stove will make that kind of sound on lighting but thats down to the air draw through it while the primary air level is fully open.

 

Its louder than normal . You would know .

[richardwale]

Sounds like Concorde is in your liner!

[Big J]

I think boiler stoves are much more prone to chimney fires than normal stoves. We've had our stove (Champion Stoves, Dominator 20kw) for 5 years now, put 35-40 cube a year through it (mostly softwood now) and I've not swept the chimney in that time. I've seen no reduction in flue performance in that time and seen no evidence of any chimney fires. We chuck all sorts of rubbish on the fire too (nappies being the main one) and it incinerates everything with no issues. Due to the size of the stove, it tends to always be burning on the hotter end of the safe range of operation, so I reckon the flue temp is high all the way to the top. It's a clay lined flue.

[Alycidon]

Has David Randleson or Greg at Esse been spoken to ?,  if not I suggest you do so,  they are on Extension 4.

 

Smoke coming back into the room is always poor flue performance,  from memory you need at least 12pa from from the flue to pull the gases around the ovens,   this is somewhat higher that is usually required for stoves.   Why this is could be a short flue,  changes in direction of the flue,  downdrafts, poor quality fuel or running the stove closed down for long periods thus not maintaining heat in the flue.  An overly long flue of say 11 or 12m could also cause cold plugging at the top.  

 

Was the stove installed and signed off by a Hetas engineer,  ( there are other self certificating schemes which are acceptable) ,  if so I assume you have called them in to check it.  Has anyone checked the flue draft reading?,  thats usually the first port of call assuming the fuel issue has been cleared.  If the reading is below 12PA then it needs improving,  typically with a wind driven rotary cowl. 

 

Which Esse model is it ?, ( I am an Esse dealer),  if with a boiler running CH then has a Boiler Control unit been fitted,   this allows the fire/cooker to get to to temperature before it allows cold water into the water jacket.   You dont usually fit a BCU on a DHW boiler as they are an indirect system.   So the water running through the boiler heats water in a tank by warming the pipes,   so water running through the boiler does not appear in your bath.  As there is far less water to heat this allows the cooker to get up to operating temp fairly fast,

 

16% is the maximum logs mc advised to use,   most KD I have seen is around 20%,  thats why I bang on about it.  Are the logs of a suitable diameter,  125mm/ 150mm average should be Ok.

 

One final thought,  I have seen a flue liner blocked solid in only six weeks of burning wet wood,  liner had to be replaced.  If you have been burning wet wood this may be the issue.

 

A

Edited February 13, 2018 by Alycidon