Co2 from house watter heater & furnace ?

[Jimmy James]

I was reading in one of the books, that you can use the Co2 from your house gas Furnace and watter heater.
Is this a good idea ?:holysheep:

 

[ozzydiodude]

No the exhaust gases have alot of Carbon Monoxide that can kill humans and pets quickly. As long as you can exchange the air in the grow room there will be plenty of CO2 for the plants to grow.