Ah that toasted newspaper smell! We had a problem like this with a wood burning stove, advised to increase the chimney length with an extra length of flue. Ended up getting a pellet burner instead. In an old house in France there was a bar strategically placed up the chimney supposedly to stop this happening and to block down drafts. Never had a problem so maybe it worked, but am not entirely convinced.
Cold plugs in chimneys and Clearblue log/multifuel burners
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Not a great fan of the Clearviews, they were ahead of the game when they came out, but design stagnated and others have caught up. Your sweep knows his stuff, the big problem is the rear outlet, as it is for all stoves not just the Clearview.
You've tried all the usual tricks and might have to settle for the Guardian or waiting for a change in the weather. There is one other option but costly, replace the rear Tee junction with a bend. There will still be a cold plug and hot air has to get 180 round the baffle, but it might be enough.
It's difficult to get warm air to go around the bafffle bend of 180 degrees, then hit a 90 degree Tee junction, and retain enough velocity and heat to push the plug out. Most rear exits are a Tee junction: the horizontal air hits a vertical pipe at 90 degrees to its direction and wants to stop. Further, the curve of the vertical pipe directs some of the flow back towards where it left the horizontal and effectively cuts it off, by cooling it.
If you fit a bend instead of a Tee it can resolve the problem. Regs require a soot sump, hence the use of a Tee, however there is at least one bend available now, with a tiny sump half-way round the vertical curved bend.
Any top outlet, even just a bend, helps the flow to move better, but I presume the headroom above the stove does not exist without building work mods.
The Guardians work well but are not quick, since they have to push air around and warm the Tee and the cold plug to get it to move. But they have a stand so can work hands free. - so you can stand up and drink a cuppa while waiting for it.
A decent capacity paint stripper like the Dewalt mentioned also works well but it gets tiresome holding it, or a dodgy balancing act to try hold it in place.
You've tried all the usual tricks and might have to settle for the Guardian or waiting for a change in the weather. There is one other option but costly, replace the rear Tee junction with a bend. There will still be a cold plug and hot air has to get 180 round the baffle, but it might be enough.
It's difficult to get warm air to go around the bafffle bend of 180 degrees, then hit a 90 degree Tee junction, and retain enough velocity and heat to push the plug out. Most rear exits are a Tee junction: the horizontal air hits a vertical pipe at 90 degrees to its direction and wants to stop. Further, the curve of the vertical pipe directs some of the flow back towards where it left the horizontal and effectively cuts it off, by cooling it.
If you fit a bend instead of a Tee it can resolve the problem. Regs require a soot sump, hence the use of a Tee, however there is at least one bend available now, with a tiny sump half-way round the vertical curved bend.
Any top outlet, even just a bend, helps the flow to move better, but I presume the headroom above the stove does not exist without building work mods.
The Guardians work well but are not quick, since they have to push air around and warm the Tee and the cold plug to get it to move. But they have a stand so can work hands free. - so you can stand up and drink a cuppa while waiting for it.
A decent capacity paint stripper like the Dewalt mentioned also works well but it gets tiresome holding it, or a dodgy balancing act to try hold it in place.
That's really useful, thanks.
There is a possibility of the stove top-venting with a bend instead of a 90 degree elbow, it's a modular Pumpkin Pi with an oven on top hence venting out the back, but if the oven module was removed, the flue could exit the top, and there's room in the fireplace for a less sharp bend. That's how the Apple Pi in the hallway fireplace is set up. (That would probably need an installer though, the sweep doesn't do installs).
I tried the Guardian today, set on its stand with the nozzle in the firebox, set it going and had a coffee. After 5-10 minutes, the flue beyond the bend was suitably warm and so I lit up conventionally and the fire went straight away. It was so "no hassle" compared to every other method I have tried.
Using 10 min warming with my weeding gun would work too, but one needs sit and hold it. Also, the Guardian has no combustion, so if it's a bad day and I get spillage, the worst that will come out of the rear (intake) vents is warm air.....
Today I used the Guardian to warm the flue with the vents open, it was chilly and damp and been a wet few days, typical kippering (spoke spillage) conditions. A successful test, as the flue warmed nicely then the fire lit very quickly and cleanly.
On a very bad day, perhaps the intake vents will need to be closed for the warming, and it would probably take a bit longer.
It's not a cheap solution for the initial outlay, but it's way less cost than changing (or reconfiguring) the stove. Although longer term that is probably a good route to go.
Edit: @Falstaff : this is the stove I have: https://www.defrastoves.com/products/pumpkinpie.htm
Current configuration is the "baked pumpkin" (second from left, grey), 5kW version.
But if the oven was removed, it becomes a standard Pumpkin Pi as per the one on the left, and then the flue can exit the top. The issue is whether it can be reconfigured after install.... they are all modular so hopefully....... The stoves all have top and rear flue options, and there's plenty headroom in the fireplace.
GC
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That's downright dissappointing, and in a pretty new design. The rear exit box has been given an angled bottom to get over the vertical tee issue, so a bend probably won't make a lot of difference. Given that these were designed for yurts and glamping with a short flue it should not be suffering this problem, which is essentially a design issue.
There is another stove, made by Charlton & Jenrick which is a near copy, which I have fitted but warned the client off getting an oven for this reason, and which works fine with a top exit.
As your stove works once warmed, and your stove section cost a substantial sum, I think your best bet is to continue with the Guardian, which I am pleased to hear works.
To fit a top exit will entail either moving the stove back to line up with the flue, or putting in an offset bend which might create another cold block. In both cases it requires a qualified installer, and we ain't cheap.
There is another stove, made by Charlton & Jenrick which is a near copy, which I have fitted but warned the client off getting an oven for this reason, and which works fine with a top exit.
As your stove works once warmed, and your stove section cost a substantial sum, I think your best bet is to continue with the Guardian, which I am pleased to hear works.
To fit a top exit will entail either moving the stove back to line up with the flue, or putting in an offset bend which might create another cold block. In both cases it requires a qualified installer, and we ain't cheap.
@Pattree : Yes, it is indeed the Grenadier.... Doh from me too.....
There is room in the whole fireplace (was originally a cavernous arched thing, became clear when we pulled the old Parkray out) to remove the oven section and put a gently angled section from the top exit. As per the Apple Core install they did for us. But as you say, it's costly and improvement may not be that great vs using the Grenadier.
TBH, I am a bit disappointed that the installer didn't highlight the possible issues as he knew the stoves and had installed them before. If so I'd have gone for the version without the oven and with the top exit, I was in 2 minds about oven vs rail-for-kettle as it was...... ho hum. We live and learn.
There's colder weather forecast next week and less wind, so it will be interesting to see how the Grenadier does if it's colder, I suspect I will just need to have a bigger cup of coffee whilst it warms things up......
..... although it's not a cheap item, I figured the Grenadier was probably the lowest cost viable solution. Also, they are made in UK, are designed to be fully servicable, all the parts for them can be obtained and the reviews indicate that they last for a long time. Unlike imported cheaper alternatives, it's not got an electronic controller- basically, you plug it in and the fan runs, then there's a key switch to turn the heating element on. Once done, you key off the element and let the fan continue to run until it has cooled down.
I prefer this approach, no fancy electronics that break once obsolescent- as happened with the Webasto heater in my old van. The circuit board controller- which does the funciton of running the fan for a time after the burner has been turned off- failed. New boards are eyewateringly costly and as it was April 2020 were unobtainium due to COVID, they were only supplying emergency services with parts. So I chanced a few quid on an old unit off a popular auction site, and thankfully it worked. But if it hadn't, it would have been the end of the van heating system. (Repair of the circuit board was in principle possible, but in practice near-impossible as it was all encapsulated in a thick resin which meant that fault finding could not be done.)
Sorry, I have digressed......
GC
There is room in the whole fireplace (was originally a cavernous arched thing, became clear when we pulled the old Parkray out) to remove the oven section and put a gently angled section from the top exit. As per the Apple Core install they did for us. But as you say, it's costly and improvement may not be that great vs using the Grenadier.
TBH, I am a bit disappointed that the installer didn't highlight the possible issues as he knew the stoves and had installed them before. If so I'd have gone for the version without the oven and with the top exit, I was in 2 minds about oven vs rail-for-kettle as it was...... ho hum. We live and learn.
There's colder weather forecast next week and less wind, so it will be interesting to see how the Grenadier does if it's colder, I suspect I will just need to have a bigger cup of coffee whilst it warms things up......
..... although it's not a cheap item, I figured the Grenadier was probably the lowest cost viable solution. Also, they are made in UK, are designed to be fully servicable, all the parts for them can be obtained and the reviews indicate that they last for a long time. Unlike imported cheaper alternatives, it's not got an electronic controller- basically, you plug it in and the fan runs, then there's a key switch to turn the heating element on. Once done, you key off the element and let the fan continue to run until it has cooled down.
I prefer this approach, no fancy electronics that break once obsolescent- as happened with the Webasto heater in my old van. The circuit board controller- which does the funciton of running the fan for a time after the burner has been turned off- failed. New boards are eyewateringly costly and as it was April 2020 were unobtainium due to COVID, they were only supplying emergency services with parts. So I chanced a few quid on an old unit off a popular auction site, and thankfully it worked. But if it hadn't, it would have been the end of the van heating system. (Repair of the circuit board was in principle possible, but in practice near-impossible as it was all encapsulated in a thick resin which meant that fault finding could not be done.)
Sorry, I have digressed......
GC
Webasco is majority owned by a subsidiary of US Morgan Stanley. In the US they believe preventing you from getting parts or repairs by anyone else, and forced upgrades, and then charging as much as possible, is acceptable and the American way. Even Obama criticised Morgan Stanley for their greed.
As your stove installer probably does not sweep, and might also have made a small extra profit on the additional oven, they do not have a lot of interest/knowledge in subsequent performance.
As your stove installer probably does not sweep, and might also have made a small extra profit on the additional oven, they do not have a lot of interest/knowledge in subsequent performance.
Update on the Grenadier.
In short; IT WORKS!
Been using it in a variety of conditions. Usually takes 10-15 minutes to get the flue warm to a point of easy lighting, but the other day I had conditions very like those that cause the biggest problems. The Grenadier ran for 25-30 min to get the flue warm- but it worked.
With the flue pre-warmed, the stove lights so much easier. Whilst I would like at tome point to modify thestove to have a top outlet, for now the Grenadier is doing the job. Set up, turn on, go and make a coffee and do my emails, check flue to confirm feels warm, remove Grenadier, lay the fire and away we go.
If you have a flue that gets awkward with a fire/stove that often needs lighting on a cold morning, I strong recommend the Grenadier. No affiliation, just a satisfied user.
GC
In short; IT WORKS!
Been using it in a variety of conditions. Usually takes 10-15 minutes to get the flue warm to a point of easy lighting, but the other day I had conditions very like those that cause the biggest problems. The Grenadier ran for 25-30 min to get the flue warm- but it worked.
With the flue pre-warmed, the stove lights so much easier. Whilst I would like at tome point to modify thestove to have a top outlet, for now the Grenadier is doing the job. Set up, turn on, go and make a coffee and do my emails, check flue to confirm feels warm, remove Grenadier, lay the fire and away we go.
If you have a flue that gets awkward with a fire/stove that often needs lighting on a cold morning, I strong recommend the Grenadier. No affiliation, just a satisfied user.
GC
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