IR Primus EtaPower MF Stove--Wheiler
- Dear Mystery Monitor:
The following is the text version of my Initial Report on the Primus EtaPower MF Stove. As usual, all the cool pictures and text boxes are only included in the html version which can be found at http://www.backpackgeartest.org/reviews/test/TESTS/IR%20Primus%20EtaPower%20MF%20Stove--Wheiler/ . Thank you for your assistance with the edits on this report.
PRIMUS ETAPOWER MF STOVE
By Michael Wheiler
Initial Report: NOVEMBER 30, 2008
Field Report: NOT YET AVAILABLE
Long Term Report: NOT YET AVAILABLE
1. The Boxed Set
Name: Michael Wheiler
Location: Southeast Idaho
Email: jmwlaw AT ida DOT net
I have about 40 years experience hiking, camping, and backpacking. I have been active in the Boy Scout program as a youth and as an adult leader. I was a Scoutmaster for seven years with an active monthly outdoor program. Since being retired from that position, I still try to get out monthly. I haven't really classified myself as having a specific backpacking style. Prior to joining BackpackGearTest, my pack weight would frequently go as high as 65 pounds (29.5 kg). Since joining BackpackGearTest, I have have experienced the advantages of carrying less weight. Now, due mostly to lighter equipment, my summer pack is generally under 40 pounds (18 kg) and my winter pack is generally less than 50 pounds (23 kg). I own and have used the following backpacking stoves: MSR Pocket Rocket; MSR Dragon Fly; Brasslite Duo Alcohol Stove; Coleman Peak1 Model 400A; Camping Gaz Bleuet Micro 270; and Primus Micron Ti 2.5. My cooking varies from simply boiling water for freeze dried meals to full-course meals prepared from scratch. I also use an Outback Oven for baking.
Field Testing Environment:
Most of my camping, hiking and backpacking occurs in the southeastern Idaho area but spills over into western Wyoming and western Montana. I occasionally get into the mountains of central Idaho as well. The areas I frequent generally range from 5,500 ft (1,600 m) to 8,500 ft (2,600 m). Usually, my outdoor experiences consist of weekend and some week long backpacking trips. However, I started climbing a few years ago and I have now climbed several of Idaho's highest peaks with elevations above 12,000' (3,658 m). In 2007, I was fortunate enough to summit Mt. Rainier. The weather in southeastern Idaho is fairly typical of a high desert plain. Winters are usually cold with temperatures at times reaching -20° F (-29° C). Snow depths vary widely but are generally over 10-12 feet (3-4 m) in the high country. Early spring temperatures remain fairly cold during the morning and evening hours but warm sufficiently in the afternoons to start the thawing process.
2. The EtaPower MF Stove/Pot Set-Up With Fuel Bottle
Item: EtaPower MF
Manufacturer's Web Site: http://www.primus.se
Manufacturer Suggested Retail Price: $190.00 US
PRODUCT SPECIFICATIONS PER MANUFACTURER UNLESS OTHERWISE NOTED
Integrated cook system
Listed: 32.8 oz/932 g (with fuel pump); 29 oz/830 g (without fuel pump)
As weighed by tester:
All parts in storage bag: 2 lbs 14.4 oz/1.32 kg
Stove/pot with fuel pump but no fuel in canister: 33.9 oz/961 g
Stove/pot without fuel pump: 27.3 oz/774 g
0.35 L/12 fl oz fuel bottle: 3.1 oz/88 g
ErgoPump: 3.5 oz/99 g
2.1 L/2.2 qt EtaPower Pot with heat exchanger: 9 oz/225 g
Lid/frying pan: 5 oz/142 g
Frying pan handle: 1.6 oz/45 g
Burner base: 4.1 oz/116 g
Windscreen: 3.4 oz/96 g
Stove, fuel cable: 5.8 oz/164 g
Extra jets: Approximately 0.1 oz/3 g each (the postal scale would only measure down to 0.1 oz/3 g)
Multi-tool: 0.6 oz/17 g
Storage bag: 10 oz/283 g
Listed: 8.3 x 8.3 x 5.3 in/210 x 210 x 135 mm
As measured by tester:
In storage case: 8.75 in/22 cm (diameter) x 5.25 in/13 cm (height)
Ready for use: 8 in/20 cm (diameter) x 6.5 in16.5 cm (height)
LP gas cartridge (mixture of propane/butane mix); white gas/petrol; kerosene/paraffin
5,400-7,000 BTU/h (1,500-2,000 W)
8,000 BTU/h per the hang tag
Burn Time and Boil Time
Average Burn Time: 6+ days on a 8 oz/230 g LP canister
1 Liter/1 Qt Boil Time: 2.5 minutes (plus pre-heating time of 45-60 seconds)
3. All The Parts
The EtaPower MF arrived from North American Gear, LLC in excellent condition. On the top of the Primus box, the manufacturer claims that the EtaPower MF is "the most versatile and environmentally friendly stove." After removing the stove from the box, I examined each of the parts and compared the parts to the schematic on the front of the enclosed printed manual. There were no missing parts. I then decided to see if I could intuitively assemble the stove without referring to the instructions. With a little trial and error, I was able to properly assemble the EtaPower MF. With one exception, the stove looked like what I expected after visiting the Primus web site. The stove in the storage sack and assembled is quite a bit larger than I anticipated. However, in retrospect, given the 2.1 L/2.2 qt pot, the stove's size should not have surprised me. The storage case zips open easily and there is a zippered pocket on the interior of the top lid of the storage case which is large enough to store the extra jets, oil, multi-tool, and a small butane lighter.
The EtaPower MF is a multi-fuel stove with an integrated windscreen and cooking pot. It can burn LP gas LP gas (propane/butane mix), good quality gasoline/petrol (such as Primus PowerFuel, MSR White Gas, and Coleman Fuel), and kerosene/paraffin. However, LP gas is recommended by Primus as the ideal fuel for the stove and normally requires no priming. While unleaded gasoline/petrol can be used, Primus notes that it is extremely volatile and contains additives that leave more deposits in the fuel system. Primus also warns that leaded gasoline/petrol should not be used. Primus also notes that kerosene/paraffin burns with a smoky flame and is difficult to preheat. Each type of fuel requires a different jet. Jet 32 is used with LP gas and came pre-installed in the fuel system. Jet 28 is used for gasoline/petrol and jet 22 is used for kerosene/paraffin.
The written instructions were easy for me to read, were written in several languages, and contained the usual warnings. Of particular interest to me was this warning from Primus, "See too that the flame on the appliance is steady. The flame shall always leave the stove straight upwards. Note! Wind may press the flame down under the burner, if that happens stop the stove immediately and move it to a wind protected area." The instructions also warn, "Use Primus LP gas cartridges/fuel bottles. Any attempt to fit another type of LP gas cartridges or liquid fuel bottle may be dangerous." The EtaPower MF is not designed for use in unventilated spaces, indoors, in a tent, in a vehicle or other enclosed space.
4. The Underside Of The Base Showing Stove Connection And Bottom Of The Pot Supports
As shown in photograph 4, the underside of the base has a metal clip on one side near the base of one of the pot supports and a corresponding slot cut in the metal on the opposite side. As shown in photograph 3, the stove has a silver colored metal support with beveled ends. The burner fits into the round portion of the hole cut in the center of the base with the brass tube and fuel connection being lowered into the narrower portion of the cut-out. One side of the silver colored metal support slides into the slot and the other side fits into the clip. The slot for the stove base is shown in both photographs 4 and 5. I had to bend the clip slightly with my fingers to create a secure fit. The base is now fitted with the stove and is ready to be connected to the windscreen.
5. The Base With Pot Supports Open And Windscreen Attached
Photograph 5 shows the base attached to the windscreen without the stove attached. It is best to attach the stove to the base before connecting the windscreen. With the pot supports in the closed position, push the base up through the opening cut in the bottom of the windscreen and turn it one quarter turn so that it locks into place under the base plate holders (the little silver tabs located to the right rear of the base of the pot holders as shown in photograph 5. Then pivot the serrated pot holders into the open position. This "secures" the windscreen to the base. However, note that the windscreen can easily be twisted back out of the "secure" position--i.e., it is not locked into place.
6. The Base, Windscreen And Stove Assembled
Once the base is connected to the windscreen, the fuel hose should be pulled out as straight as possible toward the LP gas canister or the fuel bottle. Keep the fuel hose and canister or fuel bottle away from heat that radiates from the stove when in use. The brass pre-heating tube is shown in photographs 6 and 7. It makes kind of a bent "U" loop around the burner and then connects into the brass tube to the burner by way of a screw-on-cap. This brass tube leading to the burner also houses the fuel jet for the stove. Simply grasp the round brass threaded cap and turn counter-clockwise. This unscrews the cap from the tube leading to the burner and detaches the burner from the fuel hose and pre-heating tube. The jet is located at the end of the pre-heating tube where it enters the tube to the burner. See, photograph 8. The jet is removed from the pre-heating tube with the included multi-tool or an 8 mm/3/10 in wrench. The new jet is then attached, reinserted into the brass tube leading to the burner, and the threaded cap tightened.
7. Brass Pre-heat Tube, Jet, and Burner
LIGHTING THE STOVE
LP Gas Canister Use: Check the appliance and pump seals to ensure that they are in place and in good condition before each use. Make sure the proper jet is installed in the stove for the type of fuel being used. If necessary, change the jet as described above. Keep the canister up-right. Make sure the valve on the end of the fuel line is in the closed position. Attach the valve at the end of the fuel line to the LP gas canister making sure not to cross thread the threaded valve and the screw stem on the canister. Only tighten the connection by hand. The stove is now ready to use. Turn the valve knob counter-clockwise and light the stove. On the top of the valve knob are the symbols "+" and "-" to show which direction the knob should be turned. The valve knob is made of black plastic and is shown at the top of the canister in photograph 8. Fine tune the flame by opening or closing the valve knob. When the stove is burning, Primus recommends moving the stove as little as possible because moving it may cause the flame to flare. The flame is extinguished by turning the valve knob clockwise as far as it will go. According to Primus, there will be some delay between closing the valve and the burner going out. During the field test period, I will attempt to time the delay with various fuels. Allow the stove to cool before taking it apart.
8. The Burner Attached To An LP Gas Canister
Liquid Fuel Use: Follow the general lighting instructions for the LP gas canister described above. The Primus fuel bottle should be filled to the level line with the selected fuel. Do not fill above the level line. The portion of the fuel pump that is inserted into the fuel bottle is rather large and will take up a good deal of room inside the fuel bottle. If the bottle is over-filled, when the pump is inserted, fuel will be pushed out of the top of the bottle. Thread the pump into the fuel bottle. Screw the fuel pump swivel coupling carefully into the fuel line valve until it meets the control valve O-ring. Do not over tighten. Hand tighten only. Pump 15-20 times. Pump more if the fuel in the bottle is low. Put the fuel bottle on a level surface with the text "ON" on the pump facing upwards. For starting the stove, the position of the pump in photograph 9 is incorrect as the text "OFF" on the pump is facing upwards.
9. The Fuel Bottle With Pump
Open the valve by turning the valve knob counter-clockwise and leave it open for a "short time" allowing liquid fuel to flow toward the jet. Primus does not say just how long a "short time" is. Primus simply says leaving the valve open for longer than a "short time" will cause a longer pre-heat time. I will attempt to time and report on the length of time needed to prime the stove. Check for fuel leaks at all connections. If no leaks are found, light the stove keeping your head and body away from the stove. The liquid fuel that has flowed into the stove by this time will now burn for about 45 seconds if using gasoline/petrol and about 90 seconds if using kerosene/paraffin. According to Primus, during this pre-heat period, the fuel vaporizes and at the end of this period a crackling noise will be heard. The pump valve should then be opened slowly. If the flame is yellow and relatively large, the valve should be closed and the pre-heating period allowed to continue for a short time. If the flame is relatively blue and small, the stove is ready to use.
To close down the stove and empty the fuel system, turn over the fuel bottle so that the text "OFF" on the pump is facing upwards as shown in photograph 9 above. When the flame has gone out and only air is traveling through the fuel line, close the pump valve. According to Primus, this process takes about 1 minute. I will attempt to verify the amount of time necessary to shut down the stove while using liquid fuel. Allow the stove to cool before taking it apart.
10. The Frying Pan/Lid With Handle
The pot lid can be converted into a frying pan and an aluminum handle is included with the kit for that purpose. More than once in the written instructions, Primus warns the user not to use the windscreen with the frying pan or other pots. The windscreen should only be used with the EtaPower pot. As such, the stove is secured into the base and the pot supports twisted into their fully extended positions. The frying pan or other non-EtaPower pots are then placed directly on the pot supports.
When using liquid fuel, the jet must be cleaned regularly for optimal performance. If inferior fuel is used for a "long period" of time the fuel connections will also need to be cleaned. After removing the jet as described above, use the wire on the multi-tool included in the kit to clean the interior of the jet. Remount the jet on the brass pipe and make it leak-proof by tightening it with the multi-tool. To clean out the fuel tube, using the multi-tool, unscrew the hose from the fuel connection. Pull the cleaning wire out of the fuel pipe using the multi-tool. Work the wire backwards and forwards inside the tube until the fuel connection is clean. Next, with the jet disconnected from the fuel pipe, connect the fuel pump/bottle to the pipe. Pressurize the fuel bottle with the pump, open the control valve, and flush 1/2 cup/3.65 ml of fuel through the fuel connection. Reassemble the fuel line and hand tighten. Check for leaks in the line using soapy water.
If the fuel pump fails to pressurize the fuel bottle, stretch the leather gasket slightly and oil it or apply saliva or a mineral based oil. Unscrew the pump rod and pull it out. Rub oil onto the gasket until it is soft and pliable. The these efforts do not resolve the problem, replace the leather gasket and/or replace the "O" ring on the back valve.
The EtaPower MF is easy to set-up and very versatile. Because it can use a wide variety of fuels, it can adapt to various weather conditions and altitudes. Primus asserts that the flame from the EtaPower MF can also be controlled sufficiently to simmer. This is an aspect of the stove that I have yet to test. The EtaPower MF also is large enough that it could handle the cooking needs of a small group. The pot/lid doubles as a frying pan and with the non-stick coating, should be easy to clean. However, that is also an aspect of the system that I still have to test.
11. The Stove In Storage Case
On the negative side. The EtaPower MF is heavy and large. In the blue bag on the left in photograph 11 is my usual backpacking cook system which includes a Primus Micron stove, a spice container, an 8 oz/227 g LP gas canister, a butane lighter, and a titanium pot. The EtaPower MF dwarfs the cook system I generally use. I personally would not carry a cooking system like this unless I was traveling with a group that would justify the added size and weight. Based upon size and weight alone, I would not carry this cook system as a soloist or even while traveling with one other person. However, I have been known to carry a Backpacker's Pantry Outback Oven for a group of three or four and I would consider sharing the EtaPower MF as a cook system for that size group.
This is the first integrated stove/pot system I have ever owned. As such, I am curious as to just how much the wind and cold affects the EtaPower MF. During my field use of the stove, I will report on my findings. I will also report on how diverse I can be with the meals I prepare on the EtaPower MF (and still enjoy eating what I cook).
This concludes my Initial Report on the Primus EtaPower MF stove. A Field Report containing my experiences with the EtaPower MF will be appended to this report in approximately two (2) months. I would like to thank Primus and BackpackGearTest for giving me the opportunity to test the EtaPower MF stove.
Under Inspection and Construction
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