You dont get how important this is to me. Or maybe you do.
July 1, 2009 6:38 PM   Subscribe

When I use my stove-top espresso maker on a propane stove, it doesn't work well, but when I use it on a natural gas stove it works great.

I use the exact same coffee, and espresso maker (the Bialetti) on two different stoves, one natural gas and one propane. On the propane stove I only get about half a container of coffee, it seems as if more coffee is evaporating out the top? Or steam coming out of the safety valve? I honestly dont know what is happening but there isnt much coffee but there isnt excess water left in the bottom part.

The only other difference is that the water in the propane kitchen may be a little hard.

What could be going on? What should I do?
posted by shothotbot to Food & Drink (10 answers total)
 
Propane burns hotter than natural gas, so maybe the water is boiling off rather than brewing? Have you tried turning down the flame on the propane stove?
posted by cabingirl at 6:50 PM on July 1, 2009


Are the altitudes different? Water evaporates faster and boils at lower temperatures the higher up you go.
posted by foooooogasm at 6:51 PM on July 1, 2009


The burners could be different sizes, in addition to the difference in energy density of the fuel. Could you time how long it takes to boil the same quantity of water on both stoves?
posted by electroboy at 7:03 PM on July 1, 2009


Heat is heat. But if the propane stove has natural gas orifices, it will burn way hot. It could be that your stove need to have its orifices swapped out for LPG orifices.
posted by bricoleur at 8:25 PM on July 1, 2009


Heat is heat EXCEPT when comparing propane and natural gas. And (correction) propane burns significantly COOLER than NG and there in lies an important clue to the issue. I'll leave it to the scientists to explain the whys and wherefores. (How do I know that propane burns cooler than NG?) Ask any chef in Hawaii. We don't use ANY NG here and the 'slower' flame is one of the quirks of living in Hawaii culinarians in professional kitchens must deal with.
posted by Muirwylde at 11:10 PM on July 1, 2009


If you are using it correctly then you shoduln't loose much water due to boiling off from teh top. (the Coffee up the top section should never be allowed to boil.) which would suggest that the water must be escaping via the excess pressure release valve.

I'd expect this would only happen if it was heating up VERY quickly.

I'd try using a stop watch to time the two cases from turning on until the first drop of coffee exits the top.
posted by mary8nne at 3:09 AM on July 2, 2009


i would guess that since you are in a different location, you are at a different altitude, and these pressure differences lead to more vapor being lost through the regulator on the side (not sure if these are adjustable) and to the lower evaporation temperature. try cooking it at a lower temperature so that your not blowing the steam super hard through the coffe and the valve.
posted by molecicco at 3:28 AM on July 2, 2009


(correction) propane burns significantly COOLER than NG

No, propane burns hotter. That's why if you hook an NG stove or water heater up to a propane source, you get a big-ass, scary flame. The orifices in an NG appliance are larger, to allow more gas to pass through, to make up for the fact that there are fewer BTUs in NG.

"Propane is a gas that is present in most natural gas and is the first product refined from crude petroleum. It contains approximately 2,500 Btu per cubic foot. Methane is the chief constituent of natural gas and has a heating value of about 1012 Btu per cubic foot."*
posted by bricoleur at 4:18 AM on July 2, 2009


Best answer: BTU != flame temperature != orifice size.

The orifice size is metered to the ratio of fuel to air that's needed to get the flame you are looking for.

The BTU of the fuel isn't relevant here (as a candle has way more BTU per cubic foot than any gas, but you wouldn't want to cook with it). But the BTU of the burner might be relevant- if one burner is larger than another, then you'll cook more quickly.

A bigger flame doesn't mean hotter, it just means more heat. A propane torch burns hotter than a fireplace, but you'd have a heck of a time heating a room with a torch.

This says that they burn at mostly the same temperature.
posted by gjc at 5:04 AM on July 2, 2009


Response by poster: OK, this is embarassing. It was just too hot as I could have deduced all by myself by noticing that steam was coming out of the safety valve. I moved it to a very low output burner and everything works fine.

In the interests of Science I timed how long it took to boil 1 cup of ice water on each of the home and away burners and it took almost the exactly the same amount of time, so I am still confused but can puzzle over the answer with a yummy espresso.

Thanks to all who took time out of their busy lives to help out.
posted by shothotbot at 6:46 PM on July 5, 2009


« Older Health Insurance for an unemployed recent college...   |   Book about being a prosecutor? Newer »
This thread is closed to new comments.