Alcohol Heaters ?

[Gruntled]

Dear listmates:
Do any of you have experience with an alcohol heater? I'm looking at a "Heatmate" non-pressurized, spill proof heater described at HeatMate Portable Non-Pressurized Alcohol Heater / Stove - Heaters - Swego.com
and am wondering if it gives off any unpleasant fumes and/or is relatively expensive to operate.
Thanks for your advice!
Richard
s/v Grebe, Valiant 40
Santa Barbara

[GordMay]

A 5200 BTU/h heater is roughly the equivalent of 1500 Watts.
An alcohol heater will put out a lot of water vapour, and possibly some noxious gases.
The cost of operation will depend upon which fuel you burn.

Portable alcohol heaters/stoves, release the combustions gases inside the boat; to include water vapour, carbon dioxide, and possibly formaldehyde and related species such as acetaldehyde, & carbon monoxide; depending upon which of the alcohols is burned, and it’s purity.

Complete Combustion of alcohol produces:
Pure Ethanol: C2H5OH + 3O2 → 2CO2 + 3H2O + heat
Pure Methanol: 2CH3OH + 3O2 → 2CO2 + 4H2O + heat
Pure Butanol: C4H9OH + 6O2 → 4CO2 + 5H2O + heat

[James S]

Originally Posted by GordMay

A 5200 BTU/h heater is roughly the equivalent of 1500 Watts.
An alcohol heater will put out a lot of water vapour, and possibly some noxious gases.
The cost of operation will depend upon which fuel you burn.

Portable alcohol heaters/stoves, release the combustions gases inside the boat; to include water vapour, carbon dioxide, and possibly formaldehyde and related species such as acetaldehyde, & carbon monoxide; depending upon which of the alcohols is burned, and it’s purity.

Complete Combustion of alcohol produces:
Pure Ethanol: C2H5OH + 3O2 → 2CO2 + 3H2O + heat
Pure Methanol: 2CH3OH + 3O2 → 2CO2 + 4H2O + heat
Pure Butanol: C4H9OH + 6O2 → 4CO2 + 5H2O + heat

Yeah...thats what I was gonna say

[svHyLyte]

In Santa Barbara the inside of the hull will be dripping with condensate within 20 minutes. If you have a CNG or Propane stove, buy a clay pot and up-end it over a lit burner and turn on a small fan to distribute the warmed air (or better dock-side, pick up a small electric heater!)

FWIW...

[Healer52]

As my chemistry professor used to pound into us: The only place you get complete combustion (or reaction) is on a chemistry exam....

I used to have a pressurized alcohol stove on my boat. I was quite happy to get rid of it and put in propane - it was cleaner, faster to use, easier, didn't produce the fumes or moisture. The pressurization helped achieve a closer stoichiometric ratio in the combustion over a non-pressurized burner. And it didn't flare and leave soot on the overhead.

[shipofools]

Originally Posted by Healer52

As my chemistry professor used to pound into us: The only place you get complete combustion (or reaction) is on a chemistry exam....
The pressurization helped achieve a closer stoichiometric ratio in the combustion over a non-pressurized burner. And it didn't flare and leave soot on the overhead.

had to look that up - Stoichiometry - Wikipedia, the free encyclopedia

[Healer52]

Originally Posted by shipofools

had to look that up - Stoichiometry - Wikipedia, the free encyclopedia

Sorry...the perfect ratio of fuel and air to result in complete conversion of the fuel to heat energy.

[capt_douglas]

Looks like ethanol has the lowest CO2 and water byproducts of the three. Didn't know that, so thanks Gord.

[GordMay]

Originally Posted by capt_douglas

Looks like ethanol has the lowest CO2 and water byproducts of the three...

And it's drinkable (which is a better use than burning)!!!

[Gruntled]

Excellent feedback; thanks! I'll pass. I like the clay pot idea; talk about simple. I do have a small 110 volt heater when dockside and plugged in. It's the chilly evenings and mornings when cruising our beautiful Channel Islands that I would like to make a bit more comfortable.
So, thanks again.
Richard

[GordMay]

Originally Posted by svHyLyte

... If you have a CNG or Propane stove, buy a clay pot and up-end it over a lit burner and turn on a small fan to distribute the warmed air...

... cook with it.
A stove is not a heater, even with a clay pot radiator.

Complete combustion of Propane:
C3H8 + 5 O2 ➥ 3 CO2 + 4 H2O + heat

Incomplete combustion of Propane:
2 C3H8 + 7 O2 ➥ 2 CO2 + 2 CO + 2 C + 8 H2O + heat

[jackiepitts]

We had a alcohol heater very similar to the one you were looking at and ended up giving it away. Not only are they messy and cause lots of condensation inside the boat they are also expensive to use. Propane is a better way to go if given the choice. Electric heaters work if you are a dock person but for those of us that spend alot of time on anchor they are not a good option.
Jackie

[svHyLyte]

Originally Posted by GordMay

... cook with it.
A stove is not a heater, even with a clay pot radiator.

Complete combustion of Propane:
C3H8 + 5 O2 ➥ 3 CO2 + 4 H2O + heat

Incomplete combustion of Propane:
2 C3H8 + 7 O2 ➥ 2 CO2 + 2 CO + 2 C + 8 H2O + heat

Gordo--

All the foregoing may be correct but...we used a clay-pot upended on top of the CNG stove on our 1976 Cal 2-29 for years to ward off the cold in Ayala Cove in SF; later on numeruous trips to Catalina; and. still later on, not a few nights anchored off Desoto Point during the winter break here in Florida . Once heated up, the pot radiates heat for several hours, and with that, the boat stayed quite comfortable. By comparison, a canned alcohol "heat pail" was stinky, inconvenient; and, filled the boat with humidity making everything clammy. (Whatever remains of that device is now rusting away in the deep off of Port San Luis.)

FWIW...