That's my understanding too. ~ 200' ASL here, so no problem. ... On 11/29/17, Van Horn, David wrote: > Hmm, wouldn't even start here then. 5200'+. I have friends at almost > 10,000' > > > -----Original Message----- > From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf = Of > John Gardner > Sent: Wednesday, November 29, 2017 11:15 AM > To: Microcontroller discussion list - Public. > Subject: Re: [OT] Best garage heating option > > I use an unvented 30,000 BTU NG heater for supplemental heat in > > a not terribly airtight wooden house. The heater's low-oxygen sensor > > will shut down the heater at an O2 level equivalent to 4000' ASL, and > > there is also a tipover sensor shutoff. > > The room is centrally located in the house - A ceiling fan pushes heated > > air out an open interior door into the hallway, which has bedrooms at on= e > > end, & the kitchen & dining room at the other. > > There is a separate CO alarm (AC pwr + battery b/u) which also records > > peak CO level between resets. I keep the house HVAC thermostat set a > > few degrees lower than the supplemental heater - The effect is that the > > house is comfortable & the HVAC system (a heat pump) only runs in very > > cold weather. > > This setup paid for itself last winter, so I'm fairly pleased... "8) > > ... > > > On 11/29/17, jim@jpes.com wrote: >> >> Don't want CO though do you? >> >> Regards, >> >> Jim >> >>> -------- Original Message -------- >>> Subject: Re: [OT] Best garage heating option >>> From: Sean Breheny >>> Date: Wed, November 29, 2017 10:33 am >>> To: "Microcontroller discussion list - Public." >>> >>> >>> CO2 is heavier than air but CO is slightly lighter than air (1.145 >>> g/cm^3 versus roughly 1.2 g/cm^3) >>> >>> >>> On Tue, Nov 28, 2017 at 10:31 PM, Richard Pope >>> >>> wrote: >>> >>> > Allen, >>> > Very true. With our tarp setup it was completely open at the >>> > bottom to insure that there was plenty of air for the heater and >>> > for us. Since >>> > CO2 and CO are heavier than air they would fall out of the bottom >>> > of the tarps and protect us from being poisoned by them. This is >>> > slightly different from a closed building where these can build up >>> > to toxic levels very quickly. >>> > Thanks, >>> > rich! >>> > >>> > On 11/28/2017 9:16 PM, Allen Mulvey wrote: >>> > > Much of the need for a "well ventilated area" is not so much for >>> > > fear of CO but rather a need for fuel. In a well sealed >>> > > environment you can burn off all your oxygen and asphyxiate >>> > > yourself. >>> > > >>> > > Allen >>> > > >>> > > -----Original Message----- >>> > > From: piclist-bounces@mit.edu >>> > > [mailto:piclist-bounces@mit.edu] On Behalf Of mail@crcomp.net >>> > > Sent: Tuesday, November 28, 2017 9:33 PM >>> > > To: piclist@mit.edu >>> > > Subject: Re: [OT] Best garage heating option >>> > > >>> > > RussellMc wrote: >>> > >> On 28 November 2017 at 18:49, Gary Crowell >>> > > >>> > >>> > >>> > --- >>> > This email has been checked for viruses by Avast antivirus software. >>> > https://www.avast.com/antivirus >>> > >>> > -- >>> > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >>> > View/change your membership options at >>> > http://mailman.mit.edu/mailman/listinfo/piclist >>> > >>> -- >>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >>> View/change your membership options at >>> http://mailman.mit.edu/mailman/listinfo/piclist >> >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist >> > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/cha= nge > your membership options at http://mailman.mit.edu/mailman/listinfo/piclis= t > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .