Excess co2 in basement veg room

[jungthroats]

Started vegging about six weeks ago. Using co2 tanks with a programmable controller, or I should say would be using, because the sensor rarely dips below 2000ppms. I've recalibrated the controller and checked it outdoors, the reading falls to normal atmospheric levels. It's apparent now that there is an alternate source of co2 contributing to these elevated levels. This is all hydro, so no soil. There are no pilot lights, the room is cooled and heated by a 2 ton minisplit. There is a natural gas heater for the space directly above the veg room but the room is sealed so I don't think that's a cause. I've been researching cases of elevated co2 readings in homes on indoor air quality websites and found that co2 can enter buildings through cracks in subterranean floors and walls. I'm beginning to think that might be the cause. Has anybody else experienced excessive co2 levels? What was the effect on your plants? Anything I've overlooked as far as a cause is concerned? Thanks for your help.

 

[Granger2]

CO2 is heavier than air. What CO2 levels do you have upstairs? Good luck. -granger

 

[Shmavis]

Is the space heater ventless? If possible, turn it off, pilot light too, for twenty-four hours (or more) and see what you get for readings. I recently discovered high ambient CO2 in my house as well. Even started a thread about it in the Growroom Designs & Equipment section.

I’ve been altering my environment for four to six day intervals with considerable fluctuations. For example, maintaining a difference in day and night temps of no more than a few degrees to as much as thirteen degrees. Playing with CO2 supplementation as well. One of the things I did was add a ventless natural gas space heater to the finished side of my basement. With the CO2 generator in the room off, pilot too, I was reaching 2000 PPM and above. This was with no active intake for the room, only slight negative pressure from the exhaust. The room is relatively sealed with the exception of a gap between the door and the floor. I can shut down both the generator in the room and the space heater and find readings around 600 to 900 PPM. Those numbers are actually higher without plants...

Sorry for the longwinded reply. This is something I’ve been trying to deal with too. I’d first try killing the space heater and see what you find. And as Granger mentioned, check other areas of the house. I had thought my water heater was the culprit but after a weekend of no hot water I found that wasn’t it.

Best of luck!