From: Jim Elbrecht 
Newsgroups: alt.hvac alt.home.repair misc.consumers.house
Subject: Re: unvented wall mounted gas space heater
Date: Tue, 10 Jan 2006 09:42:43 -0500

[I'm only reading alt.home.repair - so if someone comments & wants me
to see it- leave a.h.r in the crosspost list]
Don Ocean  wrote:
-snip-
>When you get cold... it will be Beautiful! ;-p Try not to kill yourself 
>and your family and purchase a vented heater. Nowhere in America can an 
>occupied space have unvented heaters. Its just plain stupid to have 
>unvented!
-snip-

A properly sized unvented unit is no problem in a *properly sized*
occupied space.     Just like with the vented units a CO & gas
detector is a wise purchase.   [and probably required by most codes]

My digital readout CO detector shows no CO in my living room with an
unvented heater.        When I had the non-digital one, the only time
it ever went off was when I was using all 4 burners and the oven in
the gas stove in an adjacent kitchen.   This was in the spring and the
unvented stove wasn't running.

My local codes have a chart of max BTU for an unvented heater for each
room size .   Check your code enforcement office and your local
utility.

Jim