Friday, 14 November 2014

My thoughts on the Primus Eta Lite

My readers will be well aware of the fact that I have been a long term user of a Jetboil Sol Ti, having purchased the original version of the Sol Ti in 2011. The pot remains in good condition and the burner (with aluminium threads) was replaced by a newer brass threaded burner in 2013. The Jetboil Sol Ti has continued to work fine. However, earlier this year I noticed the Primus Eta Lite  (soon to be renamed the Lite+) with its unusual (for me) triangular shaped burner attachment to the pot, I was somewhat intrigued. So, when a local store had it on sale I did not hesitate to buy it.

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When the package arrived I eagerly opened it, and was surprised by the feeling of “quality”, yes it felt heavier, and is, but there was something about the look of the pot, the heat exchanger (HE) fins, the burner and the way they fitted together which defined quality to me.

Comparing the connectors of the two pots, Primus on the left and Jetboil on the right.

P9070016

Below is the Sol Ti (on the left) and the Eta Lite on the right. The measurements for the pots are given in the following table.


Primus Eta PackLiteJetboil Sol Ti
Pot Diameter (cm)9.59.6
Pot Depth (cm)1111.6

What is noticeable is that both pots are essentially the same size and both will hold about 730 millilitres of water (the Jetboil pot will hold about 750 millilitre). I have found that I can easily boil 600 millilitres in the Primus pot as I can in the Jetboil pot which is sufficient for my evening meal.

P9070034

The burner head of the Primus stove is very similar to the Jetboil burner head  shown on the right.

P9070025

Now to the weights, the following comparative table provides an overview of the weights of the Jetboil Sol Ti and Aluminium (both soon to be discontinued) and the Jetboil Minimo (yet to arrive in the EU as far as I know) along with the Eta Lite. I have used John Abela’s Hikelighter website to collect some of the data along with the weights he provided for the Minimo on Backpackinglight in the USA.



Primus Eta PackLiteJetboil Sol TiJetboil Sol AlJetboil Minimo
Weight in grams
Burner151103103130
Pot 140108132158
Cover 619924
Lid48171730
Total400237261342



Of course once you have a stove you modify it to you own liking, which is what I did the Eta Lite;

1. I removed the handle, which also holds the spare pot stand (saved 24 grams)

2. I replaced the Cup Lid with the Ruta Locura CF lid (saved 41 grams). I use a cut down Trail Designs Caddy as a cup/bowl which weighs 27 grams.

PB080053-imp

The new weight of the pot, burner and lid is 335 grams, still heavier than the Jetboil  at  237 grams but something I am prepared to live with. A closer inspection of the pot shows two different types of cutouts around the HE fins (I have wondered whether this was for wind protection).

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The heat exchanger fins are welded to the pot, and the welds are wider than those on the original Jetboil, from a visual inspection it would appear that there is a 2mm weld between each fin on the base of the pot as shown in the photo below.

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I have also noted that in one of the photos of the Jetboil Minimo at BPL.com that the welding method appears to be the similar.

Use in the field:

1. Lighting the burner with the Piezo, I have read elsewhere that users have had trouble with the Piezo igniter and in the beginning I did too. But I found if the gas is flowing very slowly then the Piezo works, turning the gas on to high at the beginning did not work for me and I suspect the gas under pressure is flowing too fast for the igniter to have any effect.

2. It is apparent that the burner has a regulator as at some point no matter how far you turn the burner knob the flame does not increase, which should help with fuel economy.

3. I normally boil about 2 litres of water a day if I am cooking noodles for lunch, and have found that I use about 12 grams of gas per litre of water boiled, which is the similar to the Jetboil Sol Ti.

4. The felted fabric insulating cover around the Primus pot is nice to touch, but have noticed that it can get warm.

5. Packing wise, it is of similar dimensions to the Jetboil and with the Trail Designs caddy as a bowl, the burner, a 100 gram gas canister and burner head all fit neatly together.

PB080051-imp

6. Wind protection, I have not used the Eta Lite in windy conditions, but it is apparent that the enclosed base of the burner along with the cutouts around the heat exchanger should limit the cross winds that can play havoc with the flame. You will also note in the comparative picture of the burner heads (above) the raised area around the Primus burner head would also protect the flame from cross winds in my view.

The Jetboil burner provides a more exposed environment for the burner flame, however, in my experience in strong winds, there has been little impact on the flame and as a consequence I believe that the Eta Lite may possible fare better in a windy environment. Time will tell.

7. Another aspect I have appreciated is the ability to field service the Primus burner, something that is not possible to do with the Jetboil. Of course, you will need to carry a 6 mm spanner but at least the option exists.


I have also read that the Primus Lite+ is due out in 2015, I have been advised that the name change is a result of a claim that the “ETA” is already a registered trademark. Could it be ETA Peanut Butter?

I will update this post sometime after winter.