Primus Omnifuel II burner melting/distortion problem.

[BigMonster]

Hi guys. Had this beauty a week now and only tested it home few times, Maybe 30min of running in total on both Canister gas and Primus fuel.
I understand the burner is getting red hot, but is it normal to loose shape like that? It's much more visible in real life.





Any thoughts appriciated.

 

[Bishop]

There's a thread from 2011 about this over at ClassicCampstoves.com

Condensed version is that the flame spreader was a little tight and as it expands at a different rate to the brass you get some deformation.
No adverse effect on performance and if it really bothers you then give it whack back into shape.

 

[petrochemicals]

I would say not. Mine glowed red and never did that, what used to happen was the spreader lost shape and would fail to clip, not the cup deforming. I would email primus you may get a new burner, it sounds like the alloys a little off or the spreder is too small. If you heat it do you think it will retake its shape ?

 

[BigMonster]

No reply from Primus.
I'm asking the retailer for a replacement. If you look at the pictures you will see that the deformation affects the flame and makes it uneaven (the flame does not form a full circle). Which I suspect affects the power output and/or efficiency, also makes simmering very unstable even on canister gas.
I really like this stove as it ticks all the boxes for me, but I'm finding really hard to accept something like that after barely burning 50g of gas. You can see how important is the geometry of the burner if you pop the spreader off even a bit, the stove will fail to light.






What do you think?

 

[Leshy]

I think a refund or a swap is the answer...

First I would accept a swap , if the replacement does the same , then a refund is justified...

Hopefully it was just an odd one ...

 

[BigMonster]

Update on the story. Reply from the shop:
"...We have chased Rosker (UK distributor) again today on your behalf and they have confirmed that the stove is faulty and we will therefore issuing a refund." So it's officially a fault.

From what I have seen (one stove ordered on line, two display models at Cotswold and one delivered from Cotswold warehouse) there is a difference in flame spreaders. If you buy this stove and the spreader is almost impossible to remove with bare fingers, your burner will distort to the point it will affect the flame. My current Omnifuel from Cotswold batch have a "loose" flame spreader that rattles. I got it red hot and it did distort slightly but it's barely noticable and doesn't affect anything. I would even advise bending the arms on the spreader out a bit.

And a very interesting reply from Primus:
"Hi Mattew,
And very sorry for the late reply.
We have had more than we've been able to handle lately, and we are far behind schedule in the support mail right now.This is not the service standard we'd like offer, and not what we are known to offer in the past,
But unfortunately this is where we are at, and we're working hard on getting back on track.
I see that you have gone back to the store, and that is the correct way to handle a claim...

In General the burner gets very hot and the material gets soft when the stove is running,
and with tension of the flame spreader and having the stove running for a longer duration,
this type of deformation can occur.
But it should not happen with normal use when cooking an outdoor meal.
If the stove is run hot, it is easy to get the burner back in shape just by pressing the dents back
with the multitool (or another tool).
The hardest part is getting the flame spreader of while it is hot, but with the use of pliers it is quite easily done.
It's a bit more tricky, but it is also possible only with the use of the Multitool.
Best regards
Erik Wirén".

From one side I'm happy with their common sense approach and advice, but wouldn't be very comfortable reshaping red glowing metal on a brand new stove.
I have to say it is a wonderfull device and love how refined the ergonomics are. It I loose or kill it I will buy another one without looking around.
 

 

[BigMonster]

Update on the issue.

 

[petrochemicals]

Bend the spreader so it rattles. I would say that the spreaders are being manufactured incorrectly, a mm or two and thats what happens.

 

[rik_uk3]

http://www.ebay.co.uk/itm/QUIETSTOV...216143?hash=item4b0965d64f:g:6AAAAOxyKh5R~rpE

these work well and I can now use my OF in the shed/shack

 

[BigMonster]

I would love one of those but third of the price of the whole stove? Can't justifie it....

 

[Andy BB]

I have one of those after-market silent caps (can't remember which one now) for my one of my Omnifuels as well. Nice piece of kit. Main thing to remember with these is to let the preheat burn out completely before re-lighting, otherwise there's a risk of underburn which will ruin the cap.

 

[petrochemicals]

They do not work with diesel apparently, or parrafinn. The main advantage of an omni is the superb preheating, and that cap seems to take it away, how does it operate in the cold?. A coleman featherlite or a primus gravity seem to be just as good.

 

[Imagedude]

We had nothing but trouble with Omnifuels, both in Canada and Norway (2 separate stoves). The problem was with the fuel filter which clogged and reduced fuel flow to a trickle. Had no such problem with my MSR stoves which tend to be more reliable but sadly are much less fuel efficient.

 

[Andy BB]

Never had any problem with Omnifuels, although I did make sure to take spare filters with me just in case (never needed them though). Making sure you've got clean fuel is a must though - if necessary run it through a cloth first if in any doubt, and periodically check the fuel bottle to make sure it's not got any particles in it.

Dunno where you heard the Omnifuel doesn't work with paraffin or diesel. I normally run mine on paraffin, and it is brilliant on it. You need to make sure you've fitted the right jet for It though. I have tried diesel (uses the same jet as paraffin) , and it'll work fine if you've got nothing else, but it's a dirty fuel, and you'll need to keep an eye on the filters.

MSRs are fine, but I had a bad experience with one where the pump collapsed - a not uncommon feature of MSRs for a while. As a result, I've steered clear of them since. I also found that they tend to run best on white gas, less so with paraffin.

For a bullet-proof paraffin stove, there is nothing to touch the basic Optimus 111 roarer stove. Last November in the Arctic I fired up an old 111 I hadn't used for three or more years, complete with old paraffin left in the tank from its previous outing. Worked perfectly. Paraffin stoves need decent pre-heating though. I use alcohol on all my stoves as a pre-heater, regardless of whether its white gas or paraffin. Cuts down on some and flare-ups.

 

[petrochemicals]

The omni dawg silent cap is listed as not workable with heavier distillates like kerosine etc. Maybe this is at colder temps. But the point stands that if your going to want the silence why not get a gravity.

The thing with the omni is that the preheating is done beneath the nossle so any crap is directly there, a stove with a preheat pipe has the crap stuck to the pipe (until you knock the pipe and the crap all dislodges and blocks the nossle, i prefer the omni anyway in that regard too)

One stove that always tool my fancy was this,

http://www.primus.eu/easy-fuel

Just a gas stove but looks identical to the trangia gas burner.

 

[Andy BB]

Fair enough - when I run my omnifuels on paraffin I don't use a silent cap. Works great with white gas though.

Thing to remember though is that in the US, white gas (coleman fuel) is cheap as chips, and most of their liquid stoves are designed to run on it (Coleman, SVEA 123). Hence accessories over there tend to cater for this fuel. Also their culture is more geared towards the outdoors than in the UK, and of course their population is much bigger.

In the UK and Europe, paraffin is much cheaper, and stoves are more geared towards paraffin usage - think classic optimus and primus stoves. Personally, I prefer paraffin as I think its a safer fuel, even if it takes more priming. But I still enjoy playing with my SVEA 123, and Optimus 8R and Optimus 99 stoves, as they are not only efficient and pretty much bullet-proof, but are beautifully engineered.

 

[rik_uk3]

It works fine on paraffin, just make sure you prime the burner well.