Just bought myself a NOS PT-1 on eBay from a seller in the Netherlands. It arrived very quickly, and worked very well out of the box. I just wanted to post some numbers if others are considering using the stove. I used the stove with Coleman fuel, so roughly 13 kWh/kg energy content. The stove uses 0.65g/min (tested over 20 minutes on full blast using 13g of fuel). So if it works at 100% efficiency (I know it doesn't), the stove has an output of 0.51 kW. That's not a lot, and a 660ml kettle of water takes 15 minutes to boil - pretty much what I would expect from that sort out output. So if it's windy, you aren't going to get anywhere with this, but it's good enough to make a mug of tea when you are out and about. I think it's a very pretty piece of kit, and easy to start and to operate. With an automatic cleaning needle, there isn't really any maintenance required. Just make sure you open and close the tank cap before firing it up so that there is no vacuum in the tank, and pressure can build up quickly whilst priming. For comparison: I have an 18 year old Primus Omnifuel, running on liquid paraffin. It uses 3.5g per minute, so it has a 2.42 kW output, and boils the same 660ml kettle in 3:40 minutes. You can cook for a large family or group on this thing, which I wouldn't attempt on the PT-1. But optically, the PT-1 is a thing of beauty, and I will definitely take it out hiking to make a cuppa. Attached a photo of the PT-1 in action, and the original Russian manual (Which also is posted in the "Instructions" section here.)
A little addendum - what flabbergast me is that most people report the PT-1 to have around 6000 BTU or 1.8 - 2 kW. If mine consumes 0.65g/minute, it can't have more than 1700 BTU (0.5 kW), even if there is absolutely no loss. Are people generally optimistic about the heat output of their stoves, or did I get one with a jet that is too small?
If Omnifuel consumption and output is that what you report PT-1 burner is smaller and flame is much smaller than in Omnifuel then output must be quite a bit lower. I have used both of them but never tested nor calculated their power output. By my experience PT-1 power output is much smaller than Omnifuel's.
Oid post by Doc Mark: Svea 123 v. Optimus 99 “The BTU rating for each stove is as follows (this is from the older Optimus catalogs, by the way): SVEA 123 stoves = 4,700 BTU'd Optimus 8r, and 99 = 3,300 BTU's. My own experience with both stoves seems to easily show the power difference between them. As for regulating the flame, I like both stoves. But, the older SVEA 123's get the nod. No internal cleaning needle, though, whilst the 8R and 99 both have that feature. All good stoves, but for me, I'll take the SVEA 123, both older, and "newer" R version, over either the 99 or 8R. Just my opinion. Take care, and God Bless!” We might expect the heat output of the Primus Touristky PT 1 to be near to that of the Optimus 8R…..3,300Btu/r or approx 1kW……. Best Regards, Kerophile.
I'm the least experienced stovie in this thread, but I do own several pt-1 and I must say they are very powerful. They boil a liter of water in 6, maybe 6.5 minutes. So a radically different figure from yours. Aa for the causes, we can all chime in.
I may also add my three cents. On one tank of PT-1 I cooked rice for three people, sautéed vegetables and still brewed 3 coffees.
So there must be something wrong with mine, even though the flame looks pretty much like the photos others post.
The stated consumption is 0.2l per hour, so much more than the 0.05l per hour I have. Something must be wrong.
I can give you the following dates from my Russian PT-1. Test made in the year 2007. After preheating, the first liter of water boils after 9 minutes, a second liter boils after 6½ minutes, a third liter after 6 minutes, a fourth liter takes 10 minutes, flame gets weak and the stove is empty. This is a typical line for boiling water without a stop between. Your stove must loose pressure somewhere. Most likely at the filler gasket or at the safety valve. You can test it with lather (soapy foam) while the stove is running. A leak at the control valve would create a flame. Your manual is printed in 1992. If the filler gasket has the same age, it may have hardened. Regards Radler
Ok - I have checked the filler gasket and valve, and they appear to be airtight. When I open the filler cap a minute after I have shut down the stove, I can hear the distinct hiss of pressure escaping. I have also run the stove with the needle removed to make sure that it isn't too high and obstructing the jet, but I see no change at all. As a next step, I'm thinking of broaching the jet a tiny bit to make it a bit larger to see if that changes anything. I'm a bit wary of doing that as I can't find any spare jets on eBay, so I would like to find one first before giving that a try...
Final update. I have taken a broach to the jet (I'm a watchmaker, so I got the kit and microscope to see what I'm doing), and I now have a consumption of 1.7g per minute, which gives it a 1.3kW power input, or 4500 BTU. Boiling time is now less than half of what it was before, and I am a very happy bunny. Looks like production tolerances were quite high at the time, and you could see by the shape of the jet under the microscope that it wasn't that well made. If you attempt this yourself (only do it if your fuel consumption is less than 1.5g per minute), go slowly. I took three attempts. You can't unbroach .
The quality of all products made in the final years of the Soviet Union took a nose dive. That's valid for the pt-1, I'm sorry to say. I have a 1992 pt-2 and it's not as well built aa my older models.
Good result, no signs of running too rich. Given the age of the filler cap seal it would be worth replacing anyway- they degrade with time whether used or not. Up to you whether you do the SRV pip too- some would choose to leave well alone, others would prefer to go to the effort of replacing it, resetting the release pressure and be happier it is done.
