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IceShanty Main => General Ice Fishing Chit Chat => Topic started by: mdeutsch on Dec 31, 2010, 10:52 PM

Title: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: mdeutsch on Dec 31, 2010, 10:52 PM
So the safety guy in me made me curious. Does my Mr. Buddy heater really shut down if a low oxygen level exists, and if so, at what point?

First a little background regarding oxygen levels and the effects on the human body:
20.9 percent: Percentage of oxygen found in normal air. No effect.

15-19 percent: Decreased ability to work strenuously. May
impair coordination and may induce early symptoms with individuals
that have coronary, pulmonary, or circulatory problems.

12-15 percent: Respiration and pulse increase; impaired
coordination, perception, and judgment occurs.

10-12 percent: Respiration further increases in rate and depth;
poor judgment and bluish lips occur.

8-10 percent: Symptoms include mental failure, fainting,
unconsciousness, an ash-colored-face, blue lips, nausea, and vomiting.

6-8 percent: 8 minutes - 100 percent fatal; 6 minutes - 50
percent fatal; 4-5 minutes - recovery with treatment.

4-6 percent: Coma in 40 seconds, convulsions, respiration
ceases - death

My concern was, does the Mr. Buddy shutdown before I am going to become so incapacitated that I can't escape from my shack? So, I put my safety committee guys to work. I gave them my trusted Mr. Buddy, a full tank of propane, a fifty-five gallon drum and a four-gas (LEL, O2, CO, H2S) air monitor. They lit the heater, placed it inside of a sealed drum and monitored the air with the monitor. In 90 seconds the oxygen level fell to 16% and Mr. Buddy shutdown. They repeated the experiment two more times with nearly identical results.

So in summary, the folks at Mr. Buddy did their homework and as I expected/hoped, put the proper safeguards in place to help keep their customers, my fellow ice fishing fanatics and myself alive.

Sorry for the really long post, but keep those shacks vented and let's make sure everyone has a great, safe season.
Happy New Year!  :thumbsup:
Matt
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: iceman1267 on Dec 31, 2010, 11:03 PM
Thanks Matt I have always felt safe with my Mr. Buddy and that just reasures me.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: newincudahy on Dec 31, 2010, 11:26 PM
Nice to know. If I understand right the buddies have a low Ox sensor but doesnt do anything for C.O. and for well sealed shanties a Battery operated C.O. detector should be used. Is that correct ?
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: squ1rr31_ on Dec 31, 2010, 11:27 PM
Never had a problem man, the only way you have that kind of problem is if you have absolutely no ventilation in your shack at all. Every shack I've ever been in has plenty of vents. Unless you have a LOT of back pressure you have nothing to worry about.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: wyogator on Dec 31, 2010, 11:29 PM
Thanks Matt,  I feel reassured too.  I have never doubted that it works.  It has shut off numerous times while fishing with no noticeable effects.  I just open up the shanty to get a big rush of fresh air and turn it on again.  My concern is if the safety shutoff fails.  I am not sure how the mechanisn works, and if it is fail-proof or not.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: copperjohn on Jan 01, 2011, 12:02 AM
There is no O2 sensor and the safety shut off is undeniably simple.  When O2 levels lower there is a cooresponding shrinkage in the size of the pilot flame.  When the flame shrinks down to a certain level, the thermocouple(temperature sensitive switch) deactivates, shutting off the fuel supply to the heater.  Not enough O2 = no fuel to burn.

Don't Mess with the thermocouple!  Mods made to the unit may just make it lethal.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: mdeutsch on Jan 01, 2011, 12:16 AM
CopperJohn,
Thanks for the explanation. I wondered how that system worked, since any quality oxygen sensor I've ever seen costs several times the cost of the entire Mr. Buddy. Great advice about avoiding modifications to the thermocouple.  Matt
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: wyoutdoors on Jan 01, 2011, 12:35 AM
Excellent post sir. Now do your "boys" test flashers, augers and shacks?  :tipup:
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: mdeutsch on Jan 01, 2011, 07:11 AM
GambOOler,
I caught enough grief for dragging the Mr Buddy into my office and doing what I did. I just told everyone it was in the name of personal safety for our employees. I don't know if I could make a similar case for a flasher! Maybe for an auger though because of the extremely dangerous sharp, rotating parts? Work just might be fun after all!   
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: gulp on Jan 01, 2011, 07:18 AM
Great post and thanks for the insight. Just another reason to visit IS every day.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: Mainehazmt on Jan 01, 2011, 07:28 AM
I know what you went thru! lol   wife looked at me crazy as I calibrated my meter to check it out a few yrs ago   One thing people  on this site you will see modifications people made moving the thermocouple or making the guard to block the wind  this changes the way the flame impinges on the thermocouple thus it is going to change the results defeating the sensor  from a past post of mine:

if you move the thermocouple closer to the flame I in my own opinion changes the angle and may allow for a change in the operation of the ods

"It relies on the shift of a pilot flame away from a nozzle as the oxygen content of the combustion air decreases. A thermocouple is positioned so as to be in the flame during combustion at acceptable oxygen levels and in the unburned zone when the oxygen content is below an acceptable level." 



Heater Safety (http://www.iceshanty.com/ice_fishing/index.php?topic=119639.0)
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: mdeutsch on Jan 01, 2011, 07:37 AM
Mainehazmt,
I assumed you had already put this to the test. I told my wife about what we did at work and she thought I was a geek. I told her "it was better to be a geek than be dead, now go do some laundry"

That last part might have just been in my head. Matt
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: Mainehazmt on Jan 01, 2011, 08:12 AM
not a geek   lol  it is good practical training  use  care and calibration of the meters   in industry they really dont get to see the full potential of the meters and what they can and will do  what you did is excelent training and hopefully you documented that training   by doing it your thinking outside of the box  and can be helpful in meeting the required training    I see meter usage  confined space training  just to name 2 subjects that could add to the required refresher training   debrief on the results documentation   heck theres 2 hrs right there
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: smitty0312 on Jan 01, 2011, 08:19 AM
Very nice post, I have a buddy and just assumed it was safe....now I'm re-assured. Thankyou. Smitty
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: prospector on Jan 01, 2011, 08:35 AM
how does altitude affect the pilot burn? I fish at 4-6k ft. and was so unimpressed that I sold both units and am now using the sun flower. good post thank you.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: ih772 on Jan 01, 2011, 08:48 AM
So what will kill you first, lack of O2 or CO poisoning? That's a good experiment for your safety guys.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: mdeutsch on Jan 01, 2011, 11:42 AM
Dead is dead in my book. Probably more likely to get sick from CO poisoning over the course of a day though.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: AEffling on Jan 01, 2011, 11:51 AM
Thanks a lot for sharing that man. I was not sure about this whole thing but understand it now. Before I just swung the door open a couple of times to get some fresh air.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: 2Bonthewater on Jan 01, 2011, 11:56 AM
 :tipup:     ;D

Good Stuff..........thanks for the science experiment !!!  so cool
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: ih772 on Jan 01, 2011, 01:02 PM
Dead is dead in my book. Probably more likely to get sick from CO poisoning over the course of a day though.

What I'm wondering is if you will be killed by CO poisoning before the O2 gets too low. If that's the case then there's a false sense of safety being propagated by this thread. That's why I suggested the experiment.
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: Mainehazmt on Jan 01, 2011, 06:31 PM
get a digital co detector  they are cheap now   you can watch the numbers  and apply it
Title: Re: Mr. Buddy Heater - Oxygen Sensor
Post by: mdeutsch on Jan 01, 2011, 07:50 PM
get a digital co detector  they are cheap now   you can watch the numbers  and apply it

I was really surprised to see that some of the residential CO monitors don't alarm until around 300 ppm. In homes, many of these units are mounted out of direct line of sight and the readout isn't usually watched. Investing in of these units for in-shack use would be an excellent idea.
Title: Re: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: hollis on Jan 02, 2011, 07:59 AM
How bout bringing a canary with you? ;D  Nah he'd probably freeze first,..

Anyway I'm really sensitive to fumes. I use the Mr buddy heater but hate the smell from any combustion heater (not talking about low O2 or CO here)

 For a while I thought about setting up a Zodi heater outside my Shapple but never got to do it and it probably would eat up a lot of fuel and have to be protected from wind. I purchased one and started on that project but never finished a set up,..

And then there is all the stuff I haul out to fish,..a game warden once said that he never saw a single guy that had so much stuff hauled onto the ice. (on my modified sled) 
Title: Re: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: Mainehazmt on Jan 02, 2011, 12:19 PM
How bout bringing a canary with you? ;D  Nah he'd probably freeze first,..

And then there is all the stuff I haul out to fish,..a game warden once said that he never saw a single guy that had so much stuff hauled onto the ice. (on my modified sled) 
dont feel alone  I have wayyyy tooo much with me all the time    lucky you could find one of those!!!
Title: Re: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: badger16 on Jan 02, 2011, 12:43 PM
I have my own personal monitor for work, after reading this thread I think I'll take it in the shanty with me the next time I fish.
Title: Re: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: Rebelfisher on Jan 02, 2011, 01:27 PM
great to know! and a great heater I might add!
Title: Re: Mr. Buddy Heater - Low Oxygen Shutdown
Post by: newincudahy on Jan 02, 2011, 10:33 PM
Thats why I will bring a a CO det anyway at least for an overnighter. Better to have it an not need it than need it and not have it.