Stove statistics are they correct?

[BillQ]

I have a multi fuel stove, most of the time we use wood but we wanted the option of using solids. Its rated 4.9kw and is "ecodesign" and must;

Significantly reduce its 2.5 micron particulate emissions (aka 'PM2.5') to levels significantly lower than that of not just an open fire, but also more efficient wood stoves produced a decade ago.

 

Restrict its emissions of 'Organic Gaseous Compounds' ('OGC'), Carbon Monoxide ('CO') and Nitrogen Oxides ('Nox').

 

Provide evidence of a stove's compliance through independent testing.

 

However it occurs to me that a lot of this is very variable, engineering tolerances especially as the stove wears, installation, type of wood burned, how warmed up the box is etc etc.

 

Recently I bypassed the primary air stop and had a play around with closing it down but not going down to slumber mode. The stop is set to around 1/3rd of the full movement of the primary air arm which was surprising. 

With Ash and sycamore I could go beyond where the stop was and still get a clean burn (visually) but not with softwood which would indicate that I needed to have more primary air for softwood and less for decent hardwood. 

If I went too far I noticed the flames went a deep red with blue tinges and keeping the flue temperature steady wasn't easy and I had to open the air back up a bit. Burn times are a lot longer but we don't get overheated by the radiant heat from too much flame and are still cosy enough. 

 

Early days as yet and most of the time it sits on or around the stop area but it is handy thing to be able to bypass I think. 

 

I realise that some may be horrified that I may be putting out more particulates or bad gasses into the air but I think that the makers of the stove and laws are being over cautious. 

[Steven P]

I'd be guessing that the settings are to comply with the worst case - softwoods. Else the stove manufacturer would need to ensure compliance works with either and a variable setting of primary air - which I don't think they could do.

[GarethM]

I'll bite, so you bought too large a stove and are now butchering it ?.

[BillQ]

2 hours ago, GarethM said:

I'll bite, so you bought too large a stove and are now butchering it ?.

Nope. 

Security screw and a small metal plate are all that stops the primary air closing fully. 

When we measured the room volume and used various manufacturers (and other) online calculators and it varied between 3.5 and 4.7kw however with a 5 we can open the door and push the heat to other parts of the house. Another strange thing is they do a 5kw wide-screen stove and a 7kw stove and they are the same size. I contacted them and they said that it was just the internal parts that were different and that and other things bring us to this thread. 

 

No bite, no agenda, just curiosity 

Edited 22 hours ago by BillQ

[GarethM]

I'm aware of how they restrict them and why installers fit them.

 

The real question is why you feel the need to butcher a perfectly working stove, just saying it's for science isn't really a reason.

 

It's not going to improve it's efficiency by any great extent and would they would have designed it and sold it that way.

Edited 20 hours ago by GarethM

[Stubby]

The " security " screw and plate are there in case you live in a smokeless zone . You are supposed to have it fully open . I don't live in a smokeless zone but I opened mine up so I can control the burn with the only air slide on my stove .

[spudulike]

This all sounds a bit familiar. we have run stoves for around 30 years, the latest one was the first with a flue damper but it needed it as the fire tends to burn pretty vigorously with everything shut down even though previous stoves could be almost put out by cutting back the air getting through via the dampers.

 

I was convinced this wasn't right as logs just burnt away far too fast and one night, stuffed tin foil in the top air wash damper and there it was, the fire became starved of air so I made myself a plate that cut the air wash down considerably and now get a far more controllable burn down to slumber and the glass remains very clean. The characteristics of the burn completely changed and now the wood lasts with no adverse effects.

 

All I can surmise is that manufacturers now leave an intentional amount of air entering the combustion chamber to achieve eco figures even if the stove is fully closed so a nice clean "eco" burn is achieved.

It is most likely that the average fella in the street is viewed an idiot and has no idea of how a stove should work, look, react and be controlled/adjusted. 

 

[BillQ]

2 hours ago, GarethM said:

The real question is why you feel the need to butcher a perfectly working stove, just saying it's for science isn't really a reason.

I don't see how it is butchering, if I lived outwith a smoke controlled area it wouldn't be there, however I am using wood that is dry and suitable for burning in it.

I worked in engineering until I was in my 30's, and to an extent until I retired, and even the machinery that should have been identical due to how they were constructed needed to be run slightly differently. A metal box with insulation is not or cannot be the same as a boiler/evaporator/pump or whatever even the chimney or flue size, diameter and construction will have a bearing on how it performs against a supposedly identical unit in another setting.

I don't use rubbish fuel such as pallets,  sterling board, old fences or even unknown 60 quid dumpies of wood I just want to use my stove commensurate with the fuel I use and how warm I want to and I don't think that stove manufacturers get it right, nor have I as sometimes I have closed down too far and I get sooted glass but after a  couple of weeks I think I have it not too bad, earlier this evening it got a bit too cool so I needed to get some heat out and now we are warmer so I'll cut down the air, by having a rudimentory stop of a screw and plate, kind of like having a bolt underneath the accelerator in a car as a speed limiter.

[GarethM]

That's where your wrong, a stove that's certified to whichever scheme is supplied with them fitted as standard!.

 

Do whatever you want, but I get the impression you need to find a new hobby in your retirement.

 

As the installer will have installed it and taken those variables into consideration, but think we both know you fitted it.

[BillQ]

13 hours ago, GarethM said:

9 hours ago, GarethM said:

That's where your wrong, a stove that's certified to whichever scheme is supplied with them fitted as standard!.

 

Do whatever you want, but I get the impression you need to find a new hobby in your retirement.

 

As the installer will have installed it and taken those variables into consideration, but think we both know you fitted it.

 

It is fitted with a limiter, yes but you are wrong about who fitted it, it was a HETAS registered fitter that was provided through the stove supplier. 

 

I really don't know what you think I'm doing but I would prefer that you either explain or shut up.